This process will only add fonts to whichever user account is currently being used.
True Type Fonts(TTF) and Open Type Fonts(OTF) will both work.
Create a folder in user directory(~) and name it “.fonts”
$ mkdir ~/.fonts
Now, you can install your fonts by copying them into that folder. They will automagically be accessible to your applications.
To rebuild your font cache, enter at command line:
$ sudo fc-cache -f -v