How to get that ever-so-satisfying check mark and green translucent glow on your profile’s metadata?

This guide by @simon@simonwillison.net helped me get my xpat.github.io verification on Mastodon Mexican Bold. It contains some HTML code that you can customize to point to your own page.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Redirecting to github.com/simonw/</title>
<meta http-equiv="refresh" content="0; URL=https://github.com/simonw">
<link href="https://github.com/simonw" rel="me">
<link href="https://simonwillison.net/" rel="me">
<link href="https://fedi.simonwillison.net/@simon" rel="me">
</head>
<body style="margin: 0; padding: 0">
<a
href="https://github.com/simonw"
style="
display: block;
height: 100vh;
width: 100vw;
margin: 0;
padding: 0;
color: white;
"
>
github.com/simonw
</a>
</body>
</html>
I’d already created a GitHub repository xpat.github.io and had it serving a static site that I made with Flutter several years ago as a test. I deleted almost all that was there – especially the CNAME file that contained an earlier pointer to pinche.website. (Note to self: that’s why, at first, it was redirecting to https://pinche.website and not to https://github.com/xpat which is where I keep all my repositories.)
Here’s another example by someone else: @MattHodges@mastodon.social. Mr. Hodges takes a different tack and redirects https://hodgesmr.github.io to https://matthodges.com, a static GitHub page instead of his GitHub profile page.