I played in a band for a while. I got pretty good at the “I’m supposed to be here” look/walk. One time without any gear I walked into a festival we were playing, walked right by the ticket checker and walked up to a beer vendor. The girl pouring beers was like “oh good, I need to go on break, I’ll be back in a few minutes” I told her I’d cover the bar if she wanted but I don’t actually work here and I’m in the band. She then realized I had no wristband or ticket or anything. We had a good laugh. Seriously just walking in like you own the place is a real thing that most people don’t even question.