Bring only the bare necessities. Personally I don't bring my phone with me at all, nor carry a wallet when I'm out doing that shit. I don't bring money, beer, weed, etc. I bring just enough paint, a few caps, a small towel or rag, a plastic bag, a small flashlight, a small folding knife, gloves, backpack, and my keys. It's pretty much all goes in the backpack but sometimes I carry my shit in a briefcase and wear a suit jacket and dress up so I don't 'look like' I'm into graffiti. Don't bring anything that you don't mind ditching if you have to. Definitely don't dress like you're a stereotypical graff head!! Also, if you have one, bringing your girl can be awesome because you have a lookout and you guys can come up with alibies/stories/scenarios in advance to deal with cops. You can just get into a pretend fight or act like you're about to fuck lol
I don’t bring anything except my cans and maybe a small sketch of what I’m doing. If it’s a busy place I bring a broken / cheap phone so if anyone comes past it just looks like im going to a quiet place to talk.