There are multiple ways to initiate the Outseta embeds: data attributes, links, or with code. This kitchen sink demo tries to showcase them side by side so you may get an overview.

It demos the data attribute approach for popups:

<button 
  data-o-auth="1" 
  data-mode="popup" 
  data-widget-mode="register"
>
  Login Button
</button>

The code approach for popups:

<button onClick="Outseta.auth.open({widgetMode: 'login', mode: 'popup' })">
  Login Button
</button>

And the link approach for popups:

<a href="https://snippets.outseta.com/profile#o-authenticated"
  Profile Link
</a>

In addition to the data attribute approach for on-page embeds:

<div 
  data-o-lead-capture="1"
  data-mode="embed"
  data-form-uid="z9M0zBQ4"
/>

Full demo on Code Sandbox