If you don't see this folder, launch the game once and close it to trigger folder creation. : Open The Sims 3 Launcher. Go to the Downloads tab.
Below is the full guide for installing and using the most common version (The Sims 3 mod).
: Get the Maria's.rar (or Maria.rar ) file from the Mod The Sims download page.
: This lot was originally built on paved terrain; if placed on grass, some visual adjustments may be needed to blend the edges.