No shoes on the mats
Surely this is not an unspoken rule. It's more like an unenforced rule at martial arts and some people just don't care enough or don't know why it's important to keep the mats clean.
That is the reason for this post. If you haven't figured, the mat is a strictly no shoe zone. You don't walk onto the mats with your shoes on. You take them off before you get on. No exceptions. Black belt or not you don't walk on the mats with your shoes.
This also means you don't go off the mats barefooted, walk around, go to the bathroom, to the change room and then hopping back on the mats. This is gross and you bring all crap back on the mats.
People roll on the mats and your face will end up on the mats as well. You might as well wipe your face on the bathroom floor. Seriously.
If you have to get off the mats you either put your shoes back on or you just bring a pair of slides, slippers, jandles or sandals.
It's crazy we have to enforce this and we have to tell people this.
Just respect the mats.