that a pretty narrow box. i would do 1 plant, and do some LST but not all 4 ways, i would have it so you get 3 or 4 main colas in the shape of a diamond to , or all line up in a straight line. make sure you get some hooks from above to hang you lights from as the cardboard might not hold up the weight of the lights and a fan. figure out your soil mixture, if you dont buy potting soil, but also if you but potting soil dont give nutrients for quite a while. most likely til you go into Vegetative