Spa on Gem questions

[Snagler]

We bought the spa pass. We have never used the spa on any ship. I saw folks suggesting putting your swimsuit in your carry on so you can go as soon as the spa opens. 

Wondering if there are secure lockers in the spa? Also is it like going to a YMCA? You change in a locker room and then walk around in your swimsuit? 

Sorry to be such a dunce but I have no experiemce how this works or how to prepare. 

[McFins]

In the spa on the Gem there  are separate ladies/men locker rooms with secure lockers, robes, towels, steam room, sauna, hot tub and some loungers.   

In the common co-ed area there are loungers, heated loungers, hot tub and thalassotherapy  pool.  Folks do walk around in a swimsuit or a robe.