Blow jobs

First off, I’ve only ever blown 3 guys in my life; My first boyfriend, a regrettable decision, and my current friend with benefits, all of which have left glowing reviews, but omg, there has to be a way to encourage them to cum faster! Tips? Tricks? I like being able to give him pleasure, but I can only enjoy myself for so long before it becomes a chore. Any & ALL input is appreciated ;)