For anyone new to it, here are the essentials in brief. Shower and dry off beforehand, as dry skin sweats better. Eight to fifteen minutes in the cabin is enough. What matters is not how long you stay but the cooling down afterwards, in the fresh air and under cold water. Then rest and drink, and repeat. Two to three rounds make a good rhythm.
And yes, in Germany sauna bathing is traditionally done without swimwear. A towel beneath your body is compulsory, and you keep your eyes discreetly to yourself. If you prefer to keep your swimwear on, the swimwear area at Wolke 7 is there for exactly that. If you join an Aufguss, the infusion ritual, you stay seated until the end. Opening the door halfway through counts as the gravest faux pas in the repertoire.