I typically veg for about 10-12 weeks. My first topping at the 2nd true node takes place once the plant is about 6 nodes or so high total, just so there is something substantial there to top and so the nodes that remain will at least be started off well. I tie those four branches down horizontally (or as much so as I can) N, S, E, and W and then let those four tips grow out 3-4 nodes above the tie down point and then top down at the first node above the tie. Once those 8 tops grow out enough, I tie those down spaced as evenly as possible so they all have room and then I just let them go until they are ready to flower. They grow 8 nice tops with a bunch of braching off of each. If you keep them spread out you can pretty easily maintain a nice bush in veg. I train mine to 2x2x2 right now due to the space I have, but you can train them out to even larger canopy spreads and get monster going as well.
