On hot sunny days, you can hose down the side of the house that the sun is on. Just make sure the windows are shut first! The energy of the sun will absorbed by the water's evaporation. However, it only lasts until the water is gone and will drive up your water bill if you do it a lot. Plus it won't work as well when it is cloudy or humid.
Covering the windows like Auntblabby said is crucial. Even the windows on the opposite side of the house will leach heat in, so cover those too, especially if you also follow his advice about nudity. lol
If it doesn't bother your sensory issues, a cold shower will help a lot. Or you could just pour a bottle over your head like a runner. The cooling of your head from having wet hair makes your entire body feel better.
Shaved ice is good too. Manual ice shavers are easy to find in the summer and not too expensive. A bowl's worth of melting ice in the middle of your body is pretty efficient.
_________________
"Be kind to one another" -Ellen Degeneres