How do I built trust with my snake if it' possible

[Bogertophis]

Yeah I know it's not polite to wake him up but I don't know how to take him if he isn't curled up and calm.
When he is out at night he is very aware and cautious. I am worried he won't let me take him out without a hassle when he is in the open and stretched out over the enclosure. Since this is his hunting time I am worried he will be more defensive and more eager to stand against me.

Remember, BPs are "ambush predators", so he's really not "hunting" when he's out in the open & moving around. (He might actually be looking for a place to "go".) And most will REFUSE food offered at that time. He is more defensive when out in the open, because even though snakes are predators, there are plenty of things that prey on them too. That's what he still assumes you are- a predator. But with your patience, he'll LEARN otherwise.

You just want to avoid startling him, so give him as much information as you can so he learns not to fear you. You're obviously worried that he'll turn quickly & bite you in self defense- & while for most of us long-time keepers, that's not a big deal or a big risk, I agree that's best avoided.

So take a shirt you've worn (it will have your scent on it) & dangle the sleeve onto his mid-body*- he'll probably turn & sniff that, & then decide it's a non-issue.

Then with your hand behind it, gently pet his mid-body (they know by our touch that we're not predators) & then slip it under his mid-body, & lift him out. He'll likely still be nervous, so when you restrain him, do so lightly & keep your hands under his body as much as you can. Shy snakes don't appreciate hands that are moving quickly around them- they don't understand that all these "moving parts" are part of some big friendly giant- they may perceive a stray hand as a separate threat, especially right at first, when they're first learning to feel safe around us.

*I suggested mid-body rather than confronting him "head-on" because it's friendlier, less threatening to him. OK? Predators often grab snakes by the head/neck or tail- so they are FAR more sensitive to approaches (initial touches) to those areas. Mid-body approach tells him you're not so much of a threat, especially a LIGHT touch from you. And a mid-body pick-up is needed to support his weight anyway.

Your snake won't learn to feel safe with you with one session- & no one can tell you how long it will take, but it will get MUCH easier with practice- for both of you. And if you watch him closely, you'll get much better at reading his body language- that will save you so much time & stress, I guarantee.

And one thing I NEVER do with snakes is grab them firmly behind the head to restrain them- that causes as much fear & panic in any snake as if some stranger on the street grabbed you with a choke-hold- okay? The absolute worst thing you can do (to ruin the trust you're trying to build with a snake) is to grab & tightly hold their neck. That's behaving like a predator- see? If you want a snake to trust you, you have to trust them some also... Trust is a 2-way street.