If its a tame eyas I start before hard penning when they are just starting to pump a lot and thinking about and then jumping up onto stuff in the house. I use a fairly low block, maybe 12 inches tall and do it only while I am there. Some birds will jump up there on their own, some need to be put back up numerous times. Most of them crash onto their breasts a few times, but, without enough speed to do any harm. Basically conditioning them to their leash boundary before they can bate hard. I always put the anklets on early, large downy stage. Bells a week later, helps find them if they go somewhere in the house or yard while your not looking. I never leave a young bird that can walk away free anywhere without me being there. I do leave them in the weathering yard during parts of the day while I'm doing other things and check on them regularly. They will start jumping up on low perches and start bathing when they are not near hardpenned, though I only give them a bath pan when I am there to watch. Lots of eyasses will bath by five weeks. The more things they can get used to before they can bate hard the better. They are all somewhat different, but I think postponing being tied up until they can bate hard is a setback.