There are people out there already writing about this issue, so you can always do some research about the laws where you live.
But here’s a cheat sheet of easy things to do:
1. Make sure that you have signed consent forms. Every sub, every time. There are forms you can download online. (And of course, it doesn’t hurt to have a checklist of things you consent to.)
2. If you’re not “out” as kinky and you have bruises, people are going to wonder. So make sure that you are ready to explain bruises, cuts, or other marks.
3. Always have a plan for if someone calls the cops. Screaming can cause neighbors to call them. Know what you will say.
Remember; we are all the face of the community. Each of us represents all of us when we interact with the vanilla world. BDSM has become more mainstream, but it is still shrouded in mystery to the vanilla world and some people will have a negative opinion of us from the start.
I may never meet you. We may not know each other. But we are all part of a community, and we should all try to remember that when we have interactions with the vanilla world.
Remember; safe, sane, and consensual!