I have been tying down my plants as soon as I see them shoot up in veg. From my understanding that this is the time that the plant is growing it's leaves and root system to help sustain it through the flowering. What I've been using the tie down as well as pruning to get more leaves and stems down towards the bottom creating a fat and short plant. Mainly it's been the FIM method, which is clipping the first leaves comming up out of the top of the plant. It should split and grow two shoots where you first clipped. Good luck, remember, Grow for fun, grow for pleasure, damnit just don't tell anyone.