You an easily enable CDN in Magento by following these instructions:

  1. In Magento control panel, go to Admin > Configuration > Web > Unsecure.
  2. Update the following with CDN addresses:
    • CDN URL(eg,
    • Base Media URL:
    • Base Javascript URL:
  3. Save changes
  4. Go to Magento Admin > Configuration > Current Configuration Scope: Main Website > Web > Unsecure > Base Skin URL
  5. Deselect Use Default for the Base Skin URL
  6. Update Base Skin URL:
    • Base Skin URL:
  7. Save changes

Check your sites source code that is uses CDN.
Picture links should be replaced with CDN URL addresses.