my hair is very straight, silky, and long, so this method works if your hair doesnt hold styles very well.
1. take the section of your hair you want to be in the poof, and flip it forward over your face, and spray the roots
2. flip it back over, and run a brush through it, to smooth it out
3. pinch the hair (you can also add a twist, but it makes mine uneven, though it works for others), and scoot it forwards to create the poof. (the further back your pinch, the larger it will be and vice versa)
4. use TONS of bobby pins. i normally use around 10 to make sure its secrure when i tumble
5. HAIRSPRAYYYYYYYYYY
Also, when i put my hair in the ponytail, i lay on my back on my bed, with my head hanging off the edge. I have someone push my poof forward (or do it myself), then put the rubberbands around my ponytail.
this way, i have a high and perky pony tail, but my poof does not get pulled flat when im doing my ponytail.
^^ it sounds a little weird, but ive been told i have the fiercest poof/ponytail combination in the gym!