In this video
Practical advice for anyone heading to a band audition or first rehearsal — passed on directly from Bruce John Dickinson of Little Angels, who gave this tip during an interview.
The key is the GDA check. When you arrive, set up your guitar and amp, remember to bring a stand (it looks professional and frees up your hands), get everything ready, then play a quick G, D, A to check your tuning and tone. If it sounds good, put the guitar down. That's it.
What you want to avoid is playing too much or not playing at all. The GDA check threads the needle: you've confirmed your sound works, and now you can actually talk to the people in the room. From there, the advice is to watch and listen before joining in. Let them play something first. Treat it as an audition of them too, because it is. Then when you do join in, ask what they want from you rather than guessing.
The approach works equally well for rhythm and lead guitarists and applies to any level of experience.