To generate your AdSense for mobile ad code, follow these steps:

1. Sign in to your account.
2. Visit the My ads tab.
3. From the sidebar, choose Other products.
4. Click Get started with AdSense for mobile content in the window that appears.
   
   
5. Then, click Mobile content tab which will appear in the sidebar on the left.
6. Click +New ad unit.
   
   
7. Name and customize your ad unit, then click Save and get code.
8. Copy and paste the code into the source of your mobile webpage in the location where you'd like ads to appear.

Once you've added the code to your page and saved your changes, relevant ads should appear within 48 hours.