Hand feeding is sometimes the first step in getting your cham to willingly
walk onto your hand.
When I feed my guyz, I make sure they see me holding their food, like in a
clear plastic cup, and I show it to them before dumping into their feeder, or
letting them free in the cage.
The point is to try to get your cham to associate your hand (and you) with
food and goodies, not some giant monster who wants to eat them.
If you can get them comfortable eating from your hand, you can try cup feeding. Just put a few cricks in a cup and hold it up in front of him.
If they climb inside the cup while you are holding it, then at least they trust you.
It takes tons of patience, and sometimes your arm goes numb from holding it still for so long

Most chams will at least get used to you and realize you are not a threat to them, but that does not always mean they will "like" you.