It uses in default 4 Hour 21 / 10 EMA to long or short. This is not perfect but in the long run it will profit. Works best in bull market.
LINK TO ALERT :
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.