First time sucking him off… tips?

Soooo I’ve been wanting to give my boyfriend head for a little bit now and I’m nervous. I’ve never done anything like this. He has done for physical stuff with his ex but all of this is my first time and I’m a little anxious.

I’m anxious specifically about how it’s going to taste, how it’s gonna feel, if I do a good job, and if I’m going to feel gross afterwards. If anyone has any tips, please share!