White color line is for current bar.
Green/Red color line is for last bar.
Yellow color line is for 2nd last bar.
if last crossover above 2nd last then go long
if current crossover below last then exit long
if last crossover below 2nd last then go short
if last crossover above last then exit short
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.