I liked the last post about letting your bird dictate how long it takes to want to put on a suit.
I couldn't find the video, but I saw one that looked like it was good. It was a few ways to train a bird to want to put on a flight suit. The end result was the bird nearly putting it on itself.
The first was a clicker training with food rewards. The first part was getting the bird to accept the mere presence of the suit near it with a food reward if the bird investigated the suit without being frightened.
The next part involved holding up the suit with a treat available if the bird put it's head near the opening of the suit. Click, treat if they got near it.
Next was encouraging the bird to actually place its head inside the neck hole with a treat reward and a click. Never did I see the trainer put the suit on the bird. The bird stepped into the suit for split seconds for a treat.
I don't recall the other ways completely. I believe one was tactile rewards for those cuddly birds who crave petting as much as food. Mostly they involved food rewards and a slow training with tons of positive reinforcement over the course of a month or so that rewarded the bird for taking small steps to finally wearing the suit and thinking it was a good thing.
Never seen or heard of anyone putting a suit directly on a bird with a good result.
Good luck! I can't even get my blue crown to hold his wing up and say "peek a boo!" He got the peek a boo part right, but got ticked off at me when I kept trying to teach him about the wing motion part and now won't say peek a boo anymore hehe. I would say, try not to make your bird mad at you. I am thinking I should have taught it in even smaller steps over a much longer time period. He is so smart that he spoils me. My husband got him to bow and say goodbye in 45 mins in one session with no food rewards at all. The little guy will say it and bow consistently if anyone is leaving the house! I guess birds just have to want to do something. I am guessing the reward was my hubby talking with him that much. My husband is usually very quiet, so this had to be the treat for birdie.