These screenshots are taken in Chrome on Windows but the process is identical on Mac and Linux computers.
Click the "Customize and Control" button
This will reveal a menu with lots of options. One of them will be named "Settings".
Select the "Settings" menu item
The Settings screen will now appear.
Click the "Content settings..." button.
You will then be returned to the main Settings page tab. You can now close this tab and resume your normal web browsing with your new setting.