• put on a wet tshirt. For maximum effect sit in front of a fan.
• open all the windows and blinds overnight. It’s supposed to be 24 overnight, so you want to get your house to that temp before the next day starts. Close it all up again in the morning
I've only had A/C here is Australia the past few years
same, cool loose clothes, open window if there is a breeze, fan, damp cloths to wipe face and neck and forearms , years ago damp cloths to soothe baby Miss Seagoon,
In addition, get some of that aluminium insulation they use on car windows. Layer it up to about four layers, then put it up on your windows, with the shiny side facing out.
Also, buy a cooling blanket. Put it through the wash every four hours, and wrap it around you.
Source: I feel sick but not dead, and the cat is presently purring very loudly.