STEPS
TOOLS
Open Settings.
Tap General.
Tap About.
Tap Advertising.
Toggle Limit Ad Tracking.
Clicking the Learn More link at the bottom shows additional detail on what this option does.
The creator of this guide has not included tools

How to limit ad tracking in ios 6

If you choose to limit ad tracking, apps are not permitted to use the Advertising Identifier (a non-permanent, non-personal, device identifier introduced in iOS 6) to serve you targeted ads.