Download the Wicked Whims mod files from the official source
Make sure The Sims 4 is updated to the latest version
Extract the downloaded archive if it is compressed
Open the extracted folder
Locate the `.package` file and the `.ts4script` file
Copy both files into your Sims 4 Mods folder
Place them in `Documents > Electronic Arts > The Sims 4 > Mods`
Keep the `.package` and `.ts4script` files no more than one folder deep inside Mods
Enable Mods and Script Mods in The Sims 4 game settings
Restart the game after enabling mods
Launch The Sims 4 and verify the mod is working
Update Wicked Whims after every game patch
Remove any old version files before installing a new version