It's going to take a while. You're going to need lots of patience and the knowledge that you're going to get bit. Not just once or twice, but a lot in the begining. My original Red Front Macaw hated every one, but me. However, being married, I couldn't have him constantly attacking my husband. After just a month of working with him he came around a bit. I constantly put him on my husband (after he finally stopped lunging at him). That made him seem more comfortable and to calm him down while on my husband I gave him treats while me husband held him. I also had to find his favourite treat (for most birds it pine nuts) and have my husband give it to him. We originally tried peanuts (he loves his peanuts) but he would just pretend to take it and nip his fingers. However, he eats peanuts as snack every day, so we had to bring in some thing new and exciting. Also when my husband got bit I told him to control himself, don't yell, don't fling or shake him, gently put him down and pull your finger back. Trust me, I know it is painful (ours would latch on, bite, and then twist his head while biting). but it shows that you clearly are not scared when it comes to his extreme aggressive measures. Shows dominance. Also with tricky birds I find that if you can get them out of their cage (using a something to scare them or shoo them out) that they are much more easier while on the grown, such as my african grey. From there they will usually allow you to pick them up and when they do hold them for a bit. Each time time to hold them longer and take steps towards treats and petting. It is a battle of the wills. The bird wants to know what he can do to get you to give up. Know when to give up though, or you will over stress him, but increases yor patience everyday. They're like a 2 year old. They want to know if the scream and holler or hit and kick will they get the candy. Birds will carry on and scream or bite to see if they can get what you want.