The tradition for dress in sauna room is of course - no dress. The public saunas in Finland have sauna rooms and showers separate for woman and men. But often in hotel and swimming pool there are dressing rooms or better to say relaxing rooms together for the whole group. But it is forbidden to wear a swimming suit inside the sauna because the air starts to smell bad of the wet pants. And of course all people have a shower before sauna.
Floor is a waist of good bench space.
Saunas have changed in Finland, not so much here in America. The Finnish saunas are smaller because the idea of sauna is different to day. Today the shower is outside the sauna room. All the detergents and chemicals are there. Floor space is small, only what you need to climb up to the benches.