The indicator identifies consecutive High candles and consecutive Low candles. The first candle must have an (x) pip long adjustable body for the first condition to be met, the candle must also be below or equal to the 20 stochastic level for consecutive High candles or above or equal to the 80 stochastic level for consecutive Low candles. You can set your own stochastic levels.
If the above conditions are met, then the indicator looks at candle 2. Candle 2 must also have an (x) pip long adjustable body for the condition to be met, however, it is not dependent on the stochastic levels. If conditions for candle two are met then the indicator will send an alert just after candle 1 closes and place an arrow on the chart.
For the purpose of clarity, let us divide trading styles into two types trend or range. With trend trading, if the price is going up you expect when you place your trade for it to continue in the same direction. With range trading, you expect the price to reverse so you place a trade in the opposite direction of recent movement.
So for example if three large bullish bars print according to your pip size specification and the stochastic was overbought at the time of the first bar printing are you expecting price to continue going up, and thus would like an up arrow printed on the chart, or if range trading and you would want a print down arrow at that time expecting price to go lower now that it has been in overbought territory for some time.