I want to find a new group, but I haven't got the physical space in my small apartment to host gaming sessions. What tips do you have when playing e.g. at a cafe?
The relevant guidelines boil down to:
I've gamed in a lot of places, including:
In some cases just with a small group of gamers, but I also founded the Memphis gaming club the FORGE and we went through several of these places getting a venue for a larger monthly meeting.
The trick to a bar, coffee shop, or restaurant is to ask the manager/owner/friendly employee for permission and to set expectations about what will be going on, when, how many people, how long (RPGs go longer than most people expect meetings to take), noise levels both of the participants and what you'll be willing to deal with... Many of these places have private rooms reserved for business groups or events or whatnot that you can leverage, but those are often during "normal business hours" and you may be meeting in their off times (in fact, ask them what their peak hours are and propose to use their non-peak hours). For example, you would say, "Hey, we have six people that'll buy lunch every week and not be a pain, can we use your private room for 4 hours every Sunday at 2?"
Libraries and community centers can be used, but may charge or may have rules like "you have to let anyone from the community who shows up participate". Apartment complexes have clubhouses that can be reserved (sometimes for a fee, sometimes just for a deposit).
Wherever you're using, have everyone be respectful and not get in the way, make undue noise, or mess with others (other customers, host's SO/kids/neighbors, etc.) and you'll get left alone too.
In particularly brain damaged locales they may not want role-playing or especially Dungeons & Dragons because it is a tool of the Debbil. While playing, understand that other people may not want to hear foul language, stuff about demons, etc.; keep it to a volume and content appropriate to a shared location or others will complain to whoever's in charge and whoever's in charge will kick you out. Gaming stores have a higher tolerance for unbathed annoying behavior than other places but even they have their limits, as many aspiring Asperger's sufferers have found out.
Most universities will let clubs or individuals book seminar rooms. Those are nice as they contain a big table, a black board, and easy access to snack and drink machines.
A quick list of places you may be able to play:
Things to think about when playing in a more public venue: