I keep hearing about jjimjilbangs and Korean saunas, and my Korean friends want me to go with them?

I was nervous my first time too, but it is relaxed once you know the flow. First, the bathing and sauna area is separated by gender and is nude, while the jjimjilbang common area, the heated-floor lounge with the sauna rooms, is mixed-gender and you wear the provided uniform there. At the entrance you pay, get a locker key and a set of clothes and towels. Shoes go in a shoe locker first, then you go to your gender's locker room, undress fully, and store everything. The unwritten rule in the bathing area is to shower and wash thoroughly at the seated stations before getting into the communal hot tubs, and you stay nude there; nobody is really looking, and it is completely normal and non-sexual. After soaking, you dry off, put on the uniform, and go to the unisex common area for the sauna rooms, snacks, sleeping areas, and TV, where you keep clothes on. Bring or buy a small towel, hydrate, and do not stay in the hottest rooms too long. Tattoos are generally fine in most places these days. It is one of the best-value, most relaxing things in Korea, often around 10,000 to 15,000 won, so it is worth getting over the initial nerves.