How to train tethering/auto spacing ?

Hello, I learned thethering/auto spacing recently and I wanted to incorporate it in my games (I'm silver) but I don't really know how to train it, do you have any recommendations ?

I saw it here it a TOTSSS video : "The Only SPACING Guide You Need!!! (Gumayusi Secrects)"

Of course Gumayusi can do it well and I understand how to do it, but that's mainly a feeling, so do you have ideas how can I train it ?