1. Open iTunes.
2. Click on the "Edit" menu in the menu bar at the top of the screen.
3. Select "Preferences" from the drop-down menu.
4. Click on the "Parental" tab in the Preferences window.
5. Check the box next to "Enable Parental Controls."
6. Enter a password in the "Password" field.
7. Re-enter the password in the "Verify" field.
8. Click on the "OK" button.
Once you have enabled Parental Controls, you can start censoring songs. To do this, simply right-click on a song in your iTunes library and select "Get Info" from the drop-down menu. In the Get Info window, click on the "Options" tab and select the "Censored" checkbox.
Please note that censoring songs will not prevent them from being played on your computer. It will simply remove any explicit lyrics from the songs.