How to Add Banners/Google AdSense to your Store
To add content to the edges of your store, such as banners or Google AdSense ads, visit the Design > Customise Design > Banners section of the control panel. You will then be able to select a particular region that you would like to edit, typically the left or right side of your design.
To get started, click on one of the regions that is highlighted in blue in the Step 1 panel. The Step 2 panel will then appear allowing you to add whatever content you want directly into the Text Editor. You can use the tools at the top of the Text Editor to add links and images, or alternatively you can use the TOOLS > SOURCE CODE toolbar option in the editor and paste code (such as Google AdSense) directly into the region.
Once you are happy with the content you have inserted, just click the "Save" button at the top-right of the page.
Please note that the size, position and number of editable regions in each of the available designs may vary.