We've recently had a working visitor who really seemed to enjoy the opportunity to be naked. The actual project we were on was heavy, sweaty, rock-moving-through-brush stuff, which required being heavily dressed. I keep lots of extra clothes to lend to visitors, since it's hard to fly with enough clothes for this sort of thing, and since visitors generally don't prepare for our cool evenings. Coming in for our morning break, I headed as usual straight for the shower, undressed, and washed. Some visitors drift off at that point, to take their turn later; this one simply undressed and showered while the water was still warm, then put on the bathrobe we provide along with linens and towels, and came in for a cold drink. When they noticed that I had not dressed to come in, they opened the robe and dropped it behind them, using it the way a nudist uses a towel, just to sit on. Nothing was ever said, but I though to myself, "You know nudist protocol!" When we went back out for more work, I set aside my sweaty clothes to launder, and put on fresh, offering clean clothes to the visitor as well. It surprises me how often people are willing to stay in sweaty work clothes; this visitor happily accepted two or even three clean outfits a day. I wonder if a particular reluctance to wear dirty clothes comes with nudism - when you have to wear clothes, at least they have to be clean?
And when the next visitor (who was of opposite sex) arrived, our guest cued them, at the first head-for-the-showers break, "Clothing here is on an as-needed basis." A bolder statement than I would make, but it worked to set a tone for the next person's visit, too.