Often it was as straightforward as undressing him and wanking him till he was hard, I'd wank him a little more then insist he sucked my cock hard, eventually fucking him. He was jubilant being treated like a sex slave!
I had a friend in high schoool, a couple of years older than me who was so in to me he was happy to take any position in the act of fucking. He knew I was bi but was keen to have me do as much gay stuff to him as possible.