Ok fellas, I went to my first jam session a few weeks ago. It was a ton of fun even though I did not know what I was doing. I mostly just played backup inside the chords like I was bass track. I did play two of the songs I know well and discovered I need to repeat parts A & B a few times before going to the ending. LOL This was new to me since I just play the songs like they are in our TEF files. A, B, then ending. So, I started playing along to the rhythm tracks instead and now repeat A & B parts as many times to fill the track before hitting the ending. This has helped me get better at the now 7 songs 
I know how to play. I am planning on attending another session tomorrow. I have a question though. I usually just play the banjo part the whole time through when practicing with the rhythm track. However, during the jam session, they usually passed around the melody or “break” to one of the other players around the circle. Is that something I need to plan for during the songs I choose for us to play? Do I need to play backup when I hand off the “break” to each person in the circle?
Jam Session etiquette
Yes, that’s the general idea. When someone else takes a lead, you want to play something that compliments their playing. Playing your own lead over them would sound conflicting to someone listening. This is where all of those beginner roll lessons come in handy.
Good question!
Here’s so good info:
Hi Joe it’s time for you to start checking out the lessons on backup as @BanjoBen will testify my most requested new lesson suggestion. This is where all new banjo players struggle the most. Not knowing what to do and when to do it.
I agree with all @Mark_Rocka said also learn to vamp, feel the rhythm and learn to predict chord changes. Best way to learn the latter two items is through listening with headphones and trying to play along. You’ll probably miss most of the chord changes at first unless you know the tune off by heart.
So if you are the one that chose the song how many times do you play the melody before going around the room? And then when it comes back to you, do you play melody one more time before ending?
There’s no set rule for that. Just keep in mind that the more times you play through, the more times others will feel compelled to do the same. So, if it’s a big crowd, playing through 3 times before passing it off could result in a 30 minute song. 
And if you have one more version to play when it comes back to you, take it and then motion to everyone to exit.
You’ll just have to pay attention to what the more experienced players in the room do before the song selection gets to you and then follow along.