Pack your work clothes the night before. Make sure you have all of the essentials - shoes, bra, deoderant, etc.
Put out your gym clothes the night before - just pile them onto the back or the toilet or whereever you want to dress so you don't have to bother anybody pulling out clothes.
Yes, if you can get a locker then get a locker and put your toiletries in there. A shower caddy like you used in college is super-helpful. You can just grab your stuff out of your locker and go. Even if you can't have a locker, the shower caddy is useful, since you can have it packed and in your bag (get a soft-sided mesh one). Have doubles of everthing - don't rely on taking soap out of the bathroom everyday. Have your gym soap, gym deoderant, etc. and just leave it in your bag.
Have a wet-bag to put your towel and sweaty clothes in, and your shower shoes 9 (if you need to bring them home b/c you don't have a locker).
Wash your shower-shoes once in a while.
