Personally, I train my chicks to sleep in a dog carrier under a wooly hen. I turn off the heat lamp, let them get cool, and put them in there. Within days they figure it out.
Then I put them in the run with the carrier. They are safe in a see don't touch mode for 2-3 days. They get in the carrier - I carry it to the coop. Out in the morning.
After three days - I have numerous hideouts that big birds can't fit in, a pallet just inches off the ground, one way gates, such as lifting the fencing off the ground a few inches. This allows the chicks to venture forth, and retreat when it gets too rough. I do turn the big birds out of the set up, and then give mock chases to the chicks as they venture forth - so they figure out the safety zones.
After that, I just put the carrier in the coop, un latched, in the morning, the chicks come out on their own, and after a couple of days, they will go in the coop on their own.
I do have multiple feed stations, some that the big birds cannot get too. I do have hide outs and clutter in a large 20 x 30 run, and ample space in the coop.
Mine are outside in the sunshine and fresh air at 3 weeks. Smaller chicks are less threatening to older birds. And having several chicks, makes it harder for one to take all of the attack.
Mrs K