To implement them, you'll need to generate new channel-specific ad code. Let's say you have a page with two ad units - one on the left side and one on the right. You can create a
custom channel for each one, giving them distinct names such as ‘Left_Ad' and ‘Right_Ad'. After you've regenerated the ad code for each ad unit and pasted it back into your HTML source, you can view reports for each ad unit separately.