It’s not a bad idea to tidy up, make sure you have enough TP, and post a sign on the bathroom door to identify it (you don’t want people wandering around your place in their time of need!). We also encourage gender-neutral bathroom signage as a way to offer the most inclusive experience for your guests. If you want to be proactive and happen to have an available second bathroom, offering an alternative for the artist/crew or during any extra busy times (i.e. between sets and right after the show) can help reduce waiting times and make your guests feel super special.
It is important to notify in your Space description if your facilities are unique and/or anything beyond the expected - for instance if your Space has an outhouse, or if your bathroom is not accessible, you may want to mention that to avoid any surprises.