I am not sure what type of jam you are holding and where, but here is what I can remember of an article that I read by Stephen C., an Oshawa, Ontario Blues Harp player with decades of experience. The jams that he refers to are hosted in bars, so not all of this may apply to yours. Again, I am paraphrasing heavily.

1. Be prepared. Know the songs that you are going to play, what keys they are in, whether they are slow, shuffles etc. Usually there is a house band hosting these and they need this information.

2. Bring your own instrument. A lot of house bands have a lot or money tied up in their gear, and they don't need belt buckle scratches on the back of their pride and joy Stratocaster or Jazzmaster. Drummers, go easy, leave drumheads in the condition you found them. Don't mess with the levels set by the host band on amplifiers.

3. Stay sober. A lot of people find it easier to get up in front of people if they get loosened up a bit, but keep an eye on it, nobody wants to hear the ramblings of a drunk.

4. The leader of the host band is in charge. Be prepared to do 3-4 songs, but only do a 2nd, 3rd etc. if you are invited to.

5. Be aware of what type of music is being played. Although some jams are completely "open" and welcome different styles, most tend to specialize in a particular kind of music. Hank Williams and Muddy Waters were both great artists, but most jams would support songs from one or the other.

6. Keep solos short and interact with others. Nobody wants to hear ten minute solos, play through 12 bars, watch for a nod, either to you to continue or to the harp or keyboard player etc.

7. Don't jump in unless invited. Usually if you have played a few times at a particular jam, someone may be part way through a song and think that your harp or back up vocals etc. may fit this song and they might give you the nod at which point you can jump in, don't just decide that this song can't be doen without the benefit of your special talent. Usually this is closely tied to number 3.

I am sure there are more, I can't remember them all. Hopefully this is a good start for you.

Steve Latimer