simply copy and paste the files into their specified location
search for a folder named ''SP2'' and either drag and drop or copy and paste the files from this folder and have them replace the vanilla files of the same name
make sure to run large adress aware and pick joshua as the executable
to revert the game back to vanilla go to the steam library, right click superpower 2 steam edition, go to installed files and select verify integrity of game files, you will need to do this if you want to install and play some other mod for sp2

if you found this to be insufficient information and have trouble installing the mod, contact me through discord @matejas1885