damo.f

I only put 4 on when training, but it would depend what type of elastic band and what size. Mine are just normal white rubber bands. Also a way that I was taught to check if there were enough is to, put the bands on and with one hand holding the nose you hold the wing somewhere near the end and try and lift the wing away, if it does add more until it doesn't. You can allow a bit of movement but not too much.

Hope this helps