>>105892870 (OP)
Do this every night/morning before it gets hot:
>put a fan in the window to blow the cool air in, another fan blowing the hot air out the door
>fill the freezer with water bottles
Then when it starts to get hot:
>close all windows/doors and only open them when absolutely needed
>put a sheet over doors opening to outside to keep the cool air inside when you open them
>lower the fridge cooling settings (helps if you don't keep much in it during hot spells)
>hold onto the frozen water bottles
>fill a bin with water and drop a few of the frozen water bottles in it, then point the fan at that
>don't turn on anything that generates heat (PC, TV, etc)
I do this and it stays cool inside until around late afternoon when it's already starting to cool off outside anyway.