1. Log in to your Confluence account and navigate to Apps > Html Template.
2. Under the Templates tab click on the "New" button to start creating your new Html Template.
3. In the code editor, start writing your HTML, CSS, and JavaScript code to create your Html Template.
4. As you're working on your Html Template, use the real-time preview feature to see how your Html Template will look on a Confluence page in real-time.
5. Once you're happy with your Html Template, click on the “Save” button button to save the template.
6. Publish the template by clicking on the publish button. Once Template is published it will be available in the Html Template Macro for embedding.

That's it! With these simple steps, you can create a new Html Template and start sharing your custom creations with others.