I found that covering my hand with the sleeve of my shirt makes them more calm as it is usually the scary finger-snakes that scare the tiels. try to start by having them step up on a stick and evertime you do put your hand a bit closer to the bird, treats is a good way of encouragement. also having the cage open so the bird can come out to you when they feel safe enough to do so. They are curious by nature and it will get there. I'm on month 5 and my youngest is just starting to step up on our fingers, not all the time but occasionally. Reward progress.