He wanted to come, and I said if he knew anyone else who liked the band, he should invite them. So, he invited the guy I liked! And THEN, my guy friend bailed altogether, so it was just me and this guy that I liked but didn't know very well. T

You realise that this was a set-up, right?

how do I keep things going with this guy? Like how do I keep conversations going? How can I make sure we hang out again soon (in a group would be best to begin with)?

Simply invite him out to do something.

• how to I act going forward? what can I do to be a bit more flirty, and how can I start decent conversations with him (he's a bit awkward with conversations sometimes, not just with me but with everyone)?

Just keep doing what you were doing till now.