The basic settings are 10 / 3 / 4 these are very aggressive settings, that will generate a lot of signals in all even not so volatile markets. If you need high-quality signals you settings close to 10 / 3 /21. The strongest buy/sell signals are given when the cross occurs above or below the threshold. In the 10 / 3 / 4 you threshold for buy should be around -90 values. If you use the very smoothed variant the threshold will be around -45 to -50 values.
This indicator will be first available in APEX v1 currently being beta tested.
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.