The red line is the low-price candle of the previous day.
If the price is above the lime line, open the long position (and close the short position).
If the price is below the red line, open the short position (and close the long position).
Market stop orders are recommended.
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.