topping and fimming at the appropriate time/times (starting as young as 6-7-8 nodes) will give you more bud sites and a larger canopy if done right... the topping and fimming will slow the plant down a little bit yet pays off in dividends when done at the right times as I said above; via more bud sites and along with low stress training...
tying and shaping the plant in conjunction with topping and/or fimming will pay off even more... all of these methods work by giving you more bud sites and by tying them to keep the main parts of the canopy even (the highest point of the plant will always get the most energy/biggest bud.... make all the bud sites the same height by adjusting and tying as needed throughout veg and flower and you get all big buds/main colas)...
Then you have high stress training like super cropping works a bit differently... partially breaking/snapping branches so the plant creates larger buds via the plant repairing itself and sending more energy to those partially broken/bent branches... I personally am not a fan of supercropping... it works but it think it slows the plant down more than the low stress stuff and topping...
But as all mentioned above...all in good time... try 1 thing at a time and see how it reacts when the plant is ready.. and just FYI if there's a plant that's the closest to weed...it's tomatoes... it may not require as much food but they can be shaped and trained in the same manner...
I highly suggest checking out a thread in the organic soil section (in subcools sub forum) called "mainlining" by dude named nug buckets... everything you wanna know about training is in there and will work just as good if not better in dwc rather than soil as dwc is gonna grow faster once the plant hits its stride... but until it does get moving, take it easy on her... the beginning is where we all can fuck up real nice cuz there's not a lot going on and very little you can do other than stare at it grow...and seedlings/clones only grow so fast until you can start feeding them heavier without any ill effects...
Take your time, use caution and less is more... as mentioned above...the kiss method...