You can easily change your webstore's design template in your webstore's control panel. Let me explain how you can do that step-by-step.
1. Login to your control panel through our site: Click here to login
2. In your control panel choose the template tab.
3. Choose a new template for your webstore by selecting the the template you want and clicking on "save". You can also click on "Preview" to view in a new tab a preview of your storefront with this design.

Once you save the new template you will be able to see it immediately in your webstore.
Sincerely,
-Tzipi.