>>5006422
Just the common rule of above the node, you can also follow the rule of 3 nodes before the point of cut, but that way you're getting more of a tree shaped basil.
My personal advice is that the problem isn't the pruning, weatherer soil you are using hasn't enough Nitrogen and calcium for the plant to develop big leaf, try to get a fertilizer which prioritized these elements.
Also don't compare it with TikTok video, most of them use Neapolitan Basil.