From a university health clinic. Get tested between partners. Be safe. Be smart. You don’t have to use barrier methods like condoms or dental dams — most STIs aren’t incurable and almost all (e.g. warts, heroes, HIV, syphylis, gonnorhea) can be transmitted without intercourse.
But!
If you see new partners more frequently than the average incubation period then, yeah, use barriers. And get tested.
