Um, what turns you on? We live in a world where virtually every thing and every action is someone's turn on. Do you like fat guys to fart right into your mouth? Do you want a man in high heel shoes to crush your nuts? These are things that turn other people on but, I am going to guess, don't get you hard. So, the suggestions of others might not be entirely helpful.
Figure out what you like and do those things. And how do you figure that out? Give yourself permission to explore any fantasy you like while masturbating. Be open to new sexual experiences with other people. You don't just wake up to your true sexual identity. We are constantly adding new ideas to our sexual vocabulary.
So go out there. Play safe. And have fun.