It's hard with an aviary since they don't have you around all the time so they consider you something strange. If possible, I'd spend some time in the aviary (homework, drawing, whatever) so they can get accustomed to seeing you and feel less threat. I would not use a net to catch them as that would freak them out more. Your hands would be fine. Clipping them is always an option but I'm not sure that's such a good idea with aviary birds.