Now you have a safe place to test new mods and CC.
You can now switch between the two files by renaming the one you want to play 'The Sims 4'. The game will generate a new 'The Sims 4' folder that you can rename, 'The Sims 4 - test file'. Rename the 'The Sims 4' folder to 'The Sims 4 -old' and open the game.
This can be done through doing a factory reset like in the sims 3. Create a separate game folder to try out new mods and CC in. Mods are trickier, you should always check with the mod's creator if they are compatible with the new patch before using them or try them out in a test file before adding them to your game. CC can mostly be reintroduced right away unless it's CC that is also modded (ads game features and not just a new look). Always remove all mods and CC when the game is patched.
Of course you can never be 100% sure, but by following these steps you can eliminate some potential problems. There are several ways to make sure that the mods and custom content (CC) you install are safe for your game.
