I have definitely set up a routine for my BP. The main thing I do is tap on her hide when my hand enters her tank. I do that before I do anything. It doesn't mean that I always pick her up. I might just be misting her tank or changing her water or cleaning up her waste. It's just a little thing to let her know that I am here and not a mouse.
Then I always pet her before I put the top back on. I get the impression that she is comfortable with all this. I heard from a couple ppl on this forum that snakes are creatures of habit and routine. If I can demonstrate predictable behavior she will be less stressed.
Prescenting has also been a priority. I place the FT mouse and some dirty bedding in a bowl on top of the screen of her tank about 30 minutes before feeding her. This lets her know that a mouse is entering the tank and not me.
As far as handling I waited 10 days and one feeding to handle mine. I had a lot of work to do on her tank to make her feel more secure. Once that was finished and I saw that she ate well, I went for it.
I was petrified. But I have to say it was a great experience. I really enjoyed handling her and watching her. I did my best to remain calm. This was my first time. I just scooped her up with my whole hand and then let her lay on top. She didn't ball up completely.
Good luck. I am new to the herp world....this forum is the best thing that I have come upon. Everybody here wants you to enjoy the time with your pet and will help with any ? that you have.