How do I tell someone I want to keep in contact when we barely know each other?

Just say it exactly like that, nice and easy. You seem interesting, can I add you to my socials so we can keep in touch?

Alternatively, if you recommend something (a book, an event, a store…) that this person might enjoy, there could be an opening to say “Let’s swap numbers, I’ll text you with the details.”

Well you can be gentle and timid all you want. But looking back (WAY BACK) were my younger self asking ME this question, I would tell him “screw up your courage, and ask directly if she has a boyfriend. If the answer is no be equipped to jot down your phone number (email address) on the spot. You’re young, but believe me, you want to learn NOW not to go through life wondering how things might have been had you the courage. Besides you only have 2 more opportunities, and 2 more sessions to risk rejection. It’s worth the risk. Seize the opportunity. He’s probably more afraid than you. And if that is not the case, tell him what my first girlfriend told me. “come along. Boys don’t know what they want anyway.”

Ask them for their phone number.

Tell him his band is great and ask him to keep you updated with how it is doing.

^^ “Band” is probably the high school band that they are in together.

@janbb I think you’re probably right. In that case why not just say “I like your playing, let’s keep in touch”.

Hey, why don’t we stay in touch.