Add this to your page replacing the URL with your campaign url:
<script src='https://septembed.rknight.me/sj.js?u=https://tiltify.com/@rknightuk/stjude2025'></script>
Example:
If you get the URL wrong, the embed will fall back to using the main Relay campaign. If you always want to show the Relay campaign, don't pass anything to u=.