Preview themes from the VSCode marketplace. Check out the annoucement post.
In order for your themes to show up on vscodethemes they must:
Note: Themes may take serveral days before they show up on the site, including updates to existing themes.
If you're not sure why a theme isn't showing up, feel free to open an issue.
Consult the VSCode docs for how to build your own theme.
Suggest new features or contribute to the existing discussions.