Once you have created your templates and uploaded them to the /v65html folder, you will to need to parse them. To do this, go to Settings > Designer Launch. If you don't see the Designer Launch option you may need to update your login account to be a Developer account.
Any files that are in the /v65html folder will appear as options for each layout type. Select the template/HTML file that you would like to use for each layout, then click Parse Files. Standard layout types appear at the top, while any custom layouts appear at the bottom.