With the Jazz Festival right around the corner, both aspiring and experienced jazz musicians will hear some great concerts, but there’s always a chance they might share musical conversation at a late-night jam session as well.

A jam is a curious creature. The players are assembled on the spot, the song is decided in the quickest consultation imaginable, and then the leader counts in. Sometimes the results are spectacular, occasionally they’re disastrous, and usually they’re somewhere in the middle. One thing is clear: musicians who jam regularly get better at it. Jazz is a language, and to master a language, you actually have to practice being in conversation.

As with any conversation, there are certain basic requirements to meet. If you’re keen to take on the thrill of the jam session, start by mastering one blues song and one standard. Practice with a metronome. Play major and minor scales for two octaves, and know your major, minor, and dominant chords. Once you have facility on your instrument and an understanding of basic harmonic functions, you have a solid vocabulary.

Listen to recordings. Ask a jazz musician you trust to recommend a listening list, then play along with recordings until you feel confident with the melodies and song forms. Learn the solos too—this helps you develop syntax and expressiveness. It’s also the path to developing your own unique voice.

Attitude is a huge part of the jam session. Everybody is about to invent something on the spot, so expect some nerves. Be respectful of others and of the work you’re doing together—creating real music depends on everyone supporting one another to put forward their best effort. Steve Kirby urges experienced players to go up and play with weaker ones. “It sets up karma for when you go and play with stronger ones,” he points out.

Watch how jam sessions work. See where experienced musicians stand, how they use the mics, how they turn their bodies to acknowledge the person soloing. Jamming is about getting to know other musicians—listen carefully to their musical ideas. When it’s your turn to solo, remember that you’re still in conversation so respond to what you’ve been hearing. Keep it short, especially when you’re still learning, then make eye contact with your audience when they applaud you.

Musical conversation is the very core of this art form, so getting comfortable in a jam session is a necessity for jazz musicians. There are a few regular jam sessions in the city now. Jonny Moonbeam hosts one every Thursday at the King’s Head, and the Cool Monday Night Hang at the Orbit Room just had its sixth anniversary.

Jam sessions are just as exciting for listeners. I intend to catch a few of the late-night sessions at this year’s festival—the charge of high-level invention is well worth the next day’s red eyes!