To fim or not to fim

now when my girl gets along to producing bud, first off, which is better for a bigger plant with more crop, fimming or topping? and also when is a good idea to start this process? and how often should this be done? when should i stop?

I like to FIM everylthing and anyone that gets in my way, it makes more work, but makes the best result, start as early as you can, about 18 yo is good, there is much concern amongst the educated membershaip that weed use in those under 20yo, will make you crazy, ...this I have to agree with ...but you can grow young

I like fiming because it puts limited stress on the plants and they bounce back quick.

Top as early and as often as possible. Stop topping at least a week before you switch the photoperiod.

Don't wait too long to FIM. Do it when your plant reaches about the 5th set of nodes. I prefer to FIM over topping because many times you'll end up with more colas than 2 however keep in mind that fimming will slow upward growth to a crawl and require a bit longer recovery time than topping. Fimming is less predictable than topping which always makes 2 tops- FIM could end up with 3, 4, or 5 colas.
I prefer to only FIM once then LST the branches in a trellis or SCROG net to maximize yield. There is a point at which topping or fimming becomes detrimental instead of beneficial to yield. Each time you top the branches will make smaller buds but more of them of course so if you either top 2 times or FIM once you can realize about the same yield....if you then top/FIM again the nodes break into even smaller branches & smaller buds yet more nodal areas which will not increase in size unless allowed to veg longer. Do all your training before flipping to flower but remember: your goal is to grow bud not plants. FIM, veg, and then flip them. You can supercrop during flower to try & control the stretch but that's about it.