I never feed him in his enclosure anymore for the same reasons. Too many feeder refugees living in the enclosure. I've tried feeding him in a big bin too, but after he gets a few they will always find a way to climb into his back, and I don't imagine having roach hooks in your back feels very good.

I tong feed my big guy in a smaller tub with some water.
http://youtu.be/XuyyUiaKzGc

Males are easiest to feed, as you can use tongs to dangle them by a wing tip and the texture of the wings seems to allow the frogs to to grab them easier.

For nymphs/females, you can dangle them by the wing buds, or hold them by one of the back legs.
Either way you want as much of the roach "sticking out" as much as possible.

It takes some practice (from the both of you) but once you get the hang of it, it's pretty easy.