<!-- Include the library. -->
<script
  src="https://unpkg.com/github-calendar@latest/dist/github-calendar.min.js"
></script>

<!-- Optionally, include the theme (if you don't want to struggle to write the CSS) -->
<link
   rel="stylesheet"
   href="https://unpkg.com/github-calendar@latest/dist/github-calendar-responsive.css"
/>

<!-- Prepare a container for your calendar. -->
<div class="calendar">
    <!-- Loading stuff -->
    Loading the data just for you.
</div>

<script>
    GitHubCalendar(".calendar", "your-username");
    // or enable responsive functionality
    GitHubCalendar(".calendar", "your-username", { responsive: true });
</script>