It is considered the percentage of candles with low and high closure for a certain period. Then, a moving average is built from these values. When the moving average of the ratio of tall candles to low candles is greater than the ratio of low candles to high, then long (that is, when the green line crosses the red). And vice versa - a condition for short. It also...
if price has moved up since 1 to 3 candles ago = buy
if price has moved down since 1 to 3 candles ago = sell
has internal SL & TP
4 hour charts