2. Don't Make it Awkward
Even if you have spent your formative years in a rural area, and the only unisex bathroom you've ever seen is your grandfather's outhouse, there is no reason to stare at the women staring this space with you like they're alien intruders. For the record, making jokes about the situation make you appear equally awkward.
You'll have many difficult encounters with women, but sharing a bathroom shouldn't be one of them. If this is the hardest thing you have to do today, you should re-assess your social skills.