If you'd like to build a custom HTML email template, but don't have the necessary coding skills, we recommend checking out Bee. This service allows you to create a responsive HTML email template and export it. You can then import it into Autopilot.
See below for the steps to create a template on Bee and import it into Autopilot:
Please note that the file Bee exports does not include Autopilot's editable tags. If you want the email to be editable in Autopilot you'll need to add these. If you need help with this, or would like to get a custom HTML template designed, we recommend Mail Bakery.