Instruction for adding additional Font Squirrel Fonts?

Hi

The readme.txt files states “You can add your own selectors to the fonts, and the plugin will include them on your site.”

So far, I’ve used the Webfont Generator at Font Squrrel’s website, and downloaded the webfont kit file. I extract and rename it to match the font, and then upload to the wp-content/uploads/fontmeister directory.
However the font does not show up at this stage in page wp-admin/admin.php?page=fontmeister.

What other steps do I need to take for extra fonts to show up in the list please? Seems like a great tool, but could do with some decent tutorials to go with it I think.

https://ww.wp.xz.cn/plugins/fontmeister/