European Spa Etiquette and Newbie tips

I am currently travelling around Europe and went to to the Hostel & Spa Waldkurbad in Freiburg Germany and SchwabQuellen near Stuttgart.
I can highly recommend both places but I did make a few newbie mistakes like resting my feet on the bare wood in the spa and not on my towel.

I was wondering if anyone could suggest some tips for a newbie in a Germany spa?

The links for the placs I havce been are below.

http://schwabenquellen.de/de
http://mobile.waldkurbad.de

I am currently in Cap D'Agde would be good to hear from anyone else who is currently here.