well, lots of wanna be porn stars on here!
this is of course just a guide and i except no responsibility for any choking hazards that may occur!
You wanna dt, only one way, get horny very horny, look at him like you wanna take every inch and feel it all the way, you want that same hunger you have from sex when your on top and you just need a little more!! You have to let go, give yourself up to him, and learn to relax, you wont choke, you can still breath, tell him to start slow, and you control his speed by holding his ass, he'll know by your touch when you need more or less.
lie back, let him sit on your face and play(i like 69), let him touch you too, if you're thinking about how good you feel, you wont be worrying about breathing, believe me. I dont hang my head of the bed, you'll be surprised at what you can do if you let go. Imho a blow job is as much for me as it is for him, cause i love cocks and when im horny i want one in my mouth, just tell him, and watch how horny he gets by gettin off on you wanting his dick!!