How should i initiate with a guy in the gym shower?

I’ve never been with a guy but have always been a little curious. There’s a guy I see at the gym all the time that showers after he works out. So, of course I started to shower there too. It’s not very often I see a guy and think, I would suck that guy’s cock, but he’s one.

Anyway, I was either extra horny the other day or something because I got hard in the shower and I’m pretty sure he saw. Which made me even harder. He didn’t leave though.

I’m a little introverted so I haven’t talked...

How should i initiate with a guy in the gym shower?