How to install OTF fonts?

The directory you're looking for is /usr/share/fonts/opentype. If it's not there, you can just create it. Copy your OTF files there; this will install the font for all users. Then, recreate the fonts cache with the command sudo fc-cache -f -v.

You can also install fonts per user at ~/.fonts/. It makes no difference whether they're in any sub-folders or what type they are. Mine, as an example, are organised by foundry.

Alternatively, you can just double click them, this will open them with the Font Viewer, which let's you install them with one click:

Using the standard library on Linux, the OTF fonts don't loads. Must install addictive library based on your system configuration, libotf for example.

You have to create the folder '/usr/share/fonts/opentype', then add the 'otf' file with the font that you want to include, it works for me!