I've done stand-up five times now. Each time at an open-mic night in front of 50-100 people, many of whom are there to do their own comedy. I was once invited to fill a slot at a comedy club, but I don't recall why that didn't pan out. It was going to be a Tuesday, which is "dead night", so I think I was going to get $50 and a cocktail out of it.

I go about once every two or three months. When I think I have enough material, and I have the urge to do it again.
How was it? Good. I doubt I ever was anybody's favorite comedian of the night, but I guesstimate that I usually was in the top half of the "laugh getters" each time. I had one night where I really couldn't seem to get much reaction from the crowd, but then again, EVERYBODY was having that problem. The "vibe" was just off that night. It happens.
I'm still really amateurish. I'm more or less getting good at the unbelievably basic stuff. You know, speaking so people can understand me, remembering what I'm going to say, stuff like that. My biggest problem right now is a failure to truly connect with the audience. Right now, I'm still "person telling jokes" - I'm not somebody people can connect with on some level. That's going to be tough, since my delivery is usually pretty deadpan. It's hard to connect with people when you're acting disaffected.

But it's something I can work on in my next few attempts.
What's my material? Whatever I think is engaging. I'm not always correct in my assessments. In my very first set, I did a long bit on owning a dragon as a pet, which got some polite chuckles but nothing more. I then did a joke about ninja turtles meant to segue into a section on homosexuality...and weirdly, that one throwaway joke got more laughs than anything else I said that night. They also seemed to laugh more at the gay jokes, but I think some of that was due to them loosening up after the ninja turtle joke.
My last time up, I did a bit about seeing a dog tied up outside of a butcher shop, and comparing that to chaining your child to the ticket booth out front of Disneyland. That didn't go over well at all. So I pulled out the ninja turtle joke...and again, that got the crowd back into it. I apparently need more jokes like that.
Lex