Technical analysis tools I used in my trading plan

Bollinger Bands are a technical analysis tool invented by John Bollinger in the 1980s. Having evolved from the concept of trading bands, Bollinger Bands can be used to measure the highness or lowness of the price relative to previous trades.

Bollinger Bands consist of:

a middle band being an N-period simple moving average (MA)
an upper band at K times an N-period standard deviation above the middle band (MA + Kσ)
a lower band at K times an N-period standard deviation below the middle band (MA − Kσ)
Typical values for N and K are 20 and 2, respectively. The default choice for the average is a simple moving average, but other types of averages can be employed as needed. Exponential moving averages are a common second choice. Usually the same period is used for both the middle band and the calculation of standard deviation.

Purpose
The purpose of Bollinger Bands is to provide a relative definition of high and low. By definition, prices are high at the upper band and low at the lower band. This definition can aid in rigorous pattern recognition and is useful in comparing price action to the action of indicators to arrive at systematic trading decisions.

Indicators derived from Bollinger Bands
There are two indicators derived from Bollinger Bands, %b and BandWidth.

%b, pronounced 'percent b', is derived from the formula for Stochastics and tells you where you are in relation to the bands. %b equals 1 at the upper band and 0 at the lower band. Writing upperBB for the upper Bollinger Band, lowerBB for the lower Bollinger Band, and last for the last (price) value:

%b = (last − lowerBB) / (upperBB − lowerBB)
BandWidth tells you how wide the Bollinger Bands are on a normalized basis. Writing the same symbols as before, and middleBB for the moving average, or middle Bollinger Band:

BandWidth = (upperBB − lowerBB) / middleBB
Using the default parameters of a 20-period look back and plus/minus two standard deviations, BandWidth is equal to four times the 20-period coefficient of variation.

Uses for %b include system building and pattern recognition. Uses for BandWidth include identification of opportunities arising from relative extremes in volatility and trend identification.

Interpretation
The use of Bollinger Bands varies widely among traders. Some traders buy when price touches the lower Bollinger Band and exit when price touches the moving average in the center of the bands. Other traders buy when price breaks above the upper Bollinger Band or sell when price falls below the lower Bollinger Band.[3] Moreover, the use of Bollinger Bands is not confined to stock traders; options traders, most notably implied volatility traders, often sell options when Bollinger Bands are historically far apart or buy options when the Bollinger Bands are historically close together, in both instances, expecting volatility to revert back towards the average historical volatility level for the stock.

When the bands lie close together a period of low volatility in stock price is indicated. When they are far apart a period of high volatility in price is indicated. When the bands have only a slight slope and lie approximately parallel for an extended time the price of a stock will be found to oscillate up and down between the bands as though in a channel.

Traders are often inclined to use Bollinger Bands with other indicators to see if there is confirmation. In particular, the use of an oscillator like Bollinger Bands will often be coupled with a non-oscillator indicator like chart patterns or a trendline; if these indicators confirm the recommendation of the Bollinger Bands, the trader will have greater evidence that what the bands forecast is correct.

Btw I also use BB together with MACD - moving average convergence/divergence ( use to for trend ) to enter and exit a trade. I just want to keep it simple so that it is easy to use. So far...so good for me esp use for my forex trading. So for MACD, see the below.

MACD stands for Moving Average Convergence / Divergence, a technical analysis indicator created by Gerald Appel in the late 1970s.[1] It is used to spot changes in the strength, direction, momentum, and duration of a trend in a stock's price.

The MACD is a computation of the difference between two exponential moving averages (EMAs) of closing prices. This difference is charted over time, alongside a moving average of the difference. The divergence between the two is shown as a histogram or bar graph.

Exponential moving averages highlight recent changes in a stock's price. By comparing EMAs of different periods, the MACD line illustrates changes in the trend of a stock. Then by comparing that difference to an average, an analyst can chart subtle shifts in the stock's trend.

Since the MACD is based on moving averages, it is inherently a lagging indicator. As a metric of price trends, the MACD is less useful for stocks that are not trending or are trading erratically.

Basic components
The graph above shows a stock with an MACD indicator underneath it. The indicator shows a blue line, a red line, and a histogram or bar chart which calculates the difference between the two lines. Values are calculated from the price of the stock in the main part of the graph.

For the example above this means:

MACD line (blue line): difference between the 12 and 26 days EMAs
signal (red line): 9 day EMA of the blue line
histogram (bar graph): difference between the blue and red lines
Mathematically:

MACD = EMA[fast,12] – EMA[slow,26]
signal = EMA[period,9] of MACD
histogram = MACD – signal
The period for the moving averages on which an MACD is based can vary, but the most commonly used parameters involve a faster EMA of 12 days, a slower EMA of 26 days, and the signal line as a 9 day EMA of the difference between the two. It is written in the form, MACD(faster, slower, signal) or in this case, MACD(12,26,9).

Interpretation
Exponential moving averages highlight recent changes in a stock's price. By comparing EMAs of different lengths, the MACD line gauges changes in the trend of a stock. By then comparing differences in the change of that line to an average, an analyst can identify subtle shifts in the strength and direction of a stock's trend.

Traders recognize three meaningful signals generated by the MACD indicator.

When:

the MACD line crosses the signal line
the MACD line crosses zero
there is a divergence between the MACD line and the price of the stock or between the histogram and the price of the stock
Graphically this corresponds to:

the blue line crossing the red line
the blue line crossing the x-axis (the straight black line in the middle of the indicator)
higher highs (lower lows) on the price graph but not on the blue line, or higher highs (lower lows) on the price graph but not on the bar graph
And mathematically:

MACD – signal = 0
EMA[fast,12] – EMA[slow,26] = 0
Sign (relative price extremumfinal – relative price extremuminitial) ≠ Sign (relative MACD extremumfinal – MACD extremuminitial)
[edit] Signal line crossover
Signal line crossovers are the primary cues provided by the MACD. The standard interpretation is to buy when the MACD line crosses up through the signal line, or sell when it crosses down through the signal line.

The upwards move is called a bullish crossover and the downwards move a bearish crossover. Respectively, they indicate that the trend in the stock is about to accelerate in the direction of the crossover.

The histogram shows when a crossing occurs. Since the histogram is the difference between the MACD line and the signal line, when they cross there is no difference between them.

The histogram can also help in visualizing when the two lines are approaching a crossover. Though it may show a difference, the changing size of the difference can indicate the acceleration of a trend. A narrowing histogram suggests a crossover may be approaching, and a widening histogram suggests that an ongoing trend is likely to get even stronger.

While it is theoretically possible for a trend to increase indefinitely, under normal circumstances, even stocks moving drastically will eventually slow down, lest they go up to infinity or down to nothing.

Zero crossover
A crossing of the MACD line through zero happens when there is no difference between the fast and slow EMAs. A move from positive to negative is bearish and from negative to positive, bullish. Zero crossovers provide evidence of a change in the direction of a trend but less confirmation of its momentum than a signal line crossover.

Divergence
The third cue, divergence, refers to a discrepancy between the MACD line and the graph of the stock price. Positive divergence between the MACD and price arises when price makes hits a new low, but the MACD doesn't. This is interpreted as bullish, suggesting the downtrend may be nearly over. Negative divergence is when the stock price hits a new high but the MACD does not. This is interpreted as bearish, suggesting that recent price increases will not continue.

Divergence may also occur between the stock price and the histogram. If new high price levels are not confirmed by new high histogram levels, it is considered bearish; alternately, if new low price levels are not confirmed by new low histogram levels, it is considered bullish.

Longer and sharper divergences—distinct peaks or troughs—are regarded as more significant than small, shallow patterns.

Timing
The MACD is only as useful as the context in which it is applied. An analyst might apply the MACD to a weekly scale before looking at a daily scale, in order to avoid making short term trades against the direction of the intermediate trend.[2] Analysts will also vary the parameters of the MACD to track trends of varying duration. One popular short-term set-up, for example, is the (5,35,5).

False signals
Like any indicator, the MACD can generate false signals. A false positive, for example, would be a bullish crossover followed by a sudden decline in a stock. A false negative would be a situation where there was no bullish crossover, yet the stock accelerated suddenly upwards.

A prudent strategy would be to apply a filter to signal line crossovers to ensure that they will hold. An example of a price filter would be to buy if the MACD line breaks above the signal line and then remains above it for three days. As with any filtering strategy, this reduces both the probability of false signals as well as the frequency of missed profit.

Analysts use a variety of approaches to filter out false signals and confirm true ones. As a lagging indicator, the MACD is often paired with a leading indicator, like the Relative Strength Index (RSI). Historical comparisons to similar stocks as well as a careful investigation of past price movements provide added information about how a stock tends to move.

Limitations
The MACD has often been criticized for failing to respond in very low or alternately very high volatility market conditions.[3] Since the MACD measures the divergence between averages, it can only give meaningful feedback as trends change. Thus, the MACD is less useful if the market is not trending—trading sideways or trading erratically—making sudden, dramatic, and/or countervailing moves.

In a sideways market, the divergence between averages will not have a trend to illuminate. In an erratic market, the changes will happen too quickly to be picked up by moving averages or will cancel each other out, diminishing the MACDs usefulness. A partial caveat to this criticism is that whether a market is trending or volatile is always relative to a particular timeframe, and the MACD can be adjusted to shorter or longer spans.

Finally, though some analysts trade on technical indicators alone, the abundance of experts recommend a complete work-up of a company's business sectors, financial strength, past earnings, new products, management, and institutional buying. For more traditional investors, an indicator like the MACD may be used only to support a previously determined stock choice, or to select an ideal entry-point into a fundamentally sound stock.

Signal processing theory
In signal processing terms, the MACD is a filtered measure of velocity. The velocity has been passed through two first-order linear low pass filters. The "signal line" is that resulting velocity, filtered again. The difference between those two, the histogram, is a measure of the acceleration, with all three filters applied. An MACD crossover of the signal line indicates that the direction of the acceleration is changing. The MACD line crossing zero suggests that the average velocity is changing direction