This candlestick pattern first needs to be in an uptrend and then needs to have three uptrend candles in a row. The first candle is a normal uptrend candle with a long body, then the second candle appears to have a smaller body with larger wicks but still closes above the previous day. Lastly, the third candle still closes above the previous day but has an even smaller body and large wicks.
This is a great way to begin looking at the market and see there may be a change happening. To the obvious looker, the bulls are in control, but with the bodies getting smaller and the wicks remaining high, that means that the bulls are losing their upward push.
If you are a trader or swing trader, this could be a quick insight that this may be a stock or chart you want to watch because the bulls are losing control. Some indicators to use with this would certainly be momentum, but you can also plot Bollinger Bands as this can help to let you know even more if the chart is getting over extended.
Be sure to test this on a demo account and fine tune it to fit your current investing or trading strategy. Often people find less is more so this may not fit your current setup. At the very least, have the knowledge on hand because you never know when you may need to pull it out of the toolbox. Having that extra edge is important because it can allow you to enter and exit the markets in a more timely and accurate fashion.