I'm not an expert on parrot behaivior, I've only had Blu, my B/G one year, but I have read eight or nine books about parrots. That helped alot. But what I found worked best for me was patience. Just hang out together and watch him watching you while you watch back. Take your time, and your clues from him. TRUST it seems, is the number one factor between humans and birds. Every bird is different but they all have one thing in common. They demand trust in order to feel comfortable enough to be trained. It may seem like it takes forever, but every little bit counts. I am still establishing trust with my B/G and he'll be two years old May 5th. After a year together, we've come along way. But it's taken me just as long to trust him. I feel much more confortable holding or handling him as I'm sure he feels the same. Birds sence when your being sincere or scared. Scary as it may seem to him, you probably find him scary as well. (The Beak on a B/G is Scary enough) So take your time and learn to trust each other. Don't make holding or touching him a priority, more over treat it like an end result of much earned, sometimes long awaited trust between you both. It will come. Eventually, if you just let each other have time to feel comfortable and safe together. It is worth it.
Good Luck and remember, TRUST, TIME and TOGETHERNESS.