Does the bird accept food out of your hand? If it does, great. If not, the training will be a little different.
Don't pick this bird up with a towel anymore unless it's some kind of emergency. Otherwise, you are teaching it to become afraid of and aggressive toward a towel, and you won't be able to towel it in the future without a lot of training/trouble.
Otherwise, MandyG already posted the link to Michael's article about basic training, and that's what you should read. It's a long article but it contains plenty of useful information and advice that you should use. If you go through it and implement some of the techniques from it, you will probably see results.