Thanks Hero that really explains a lot. I'm starting to understand a bit.

When and how often should I do this?
Once you have substantial foliage, there is no "start date"; it starts when your plant is mature enough

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I know moonbeam uses LST on his plants, but I think he does it too hard, what I'd do is firmly pull the plant in one direction, and it'll grow in that direction, then to the light source, that way every time it grows substantially, you can tie it down further. That's what I'm doing with a couple of my plants, seems to be working great so far. Causing as little stress as possible, the better, even slanting your pot a bit *make sure it can still drain properly*: you'll get the same effects if you lst it in combination with this method. The stems are resilient, but not nearly as much as MJ is. So in which case you have to be delicate, and the only way to do that is by 'trial and error', hopefully avoiding error as much as possible

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Pruning means to cut back foliage so that you can let substantial light hit the plant, such as removing slow growing leaves, or leaves that are growing from where you want to grow a new branch.
'Pinching' refers to cutting one branch to make it split into two. The plant will grow two shoots where you have severed the plant, but only when it's mature enough to support this kind of new growth.
Happy Growin',
James