Need help temperature

[Sneakabong]

Ok, so I'm making a bathroom into a grow room, 25 ft sq...have an air extractor which takes out a decent ammount of air, and also have an oscillating fan... had to put a cardboard over my window because of light coming from outside and dont want anyone looking in... problem is my room temperature reaches like 93 F...

any ideas on lowering the temperature without investing in more equipment? if not, what equipment should i invest in?

Is it fine to have the door open while I'm at home? will that help?

one idea i had was to fill my bathtub with cold water several times a day, when i go check on my plants...not sure if that will lower it...

please let me know any ideas and comments on my own...