Human: How do I add mods to The Sims 3? Assistant: 
Add Mods to The Sims 3
1. Navigate to http://modthesims.info/wiki.php?title=Game_Help:Installing_Sims_3_Package_Files/Setup_and_Files and click Download 
2. Extract the zip file to "Documents > Electronic Arts > The Sims 3".
3. Download a Sims 3 mods from the internet.
4. Extract the contents of the zip file containing the mod to "Documents > Electronic Arts > The Sims 3 > Mods > Packages".