First of all, it's too early to do the big defoliation.
For the moment, you need to leave some shade so that the lower branches pull up as much as possible towards the top of the canopy to find light. However, now is the time to balance the canopy by supercropping.
As for the defoliation itself, here are a few keys:
* start by cleaning only the main stem(s) when you change the light cycle
* only deal with the secondary stems when the stretch has slowed down and the flowers have appeared. This is also the time to prune the lower part of the plant, but starting with defoliation makes the job easier as you can see the structure of the plant and how far the light penetrates the canopy.
* only cut leaves that are under a branch or a large flower, not in a bud or at a node that is too young.
* only cut leaves where the stems are visible.
And if you're not reassured, don't feel obliged to carry out this defoliation.
It's a plus for compact buds, but in this case it's better not to cut too much than too little, so do what you think is reasonable and refine the technique with experience. ^^