Hey Girls, How to give the perfect BJ?

So my boyfriend says Im really good at BJ's (getting way better as he is my first and only) but he says I don't go deep enough! I know I don't but I don't know how to get deeper without gagging! I have a sensitive gag reflex and need tips on how to give him that ultimate BJ without wanting to throw up lol
Hey Girls, How to give the perfect BJ?
Post Opinion