1. You have to find the font file (example would be Rom8.pcf.Z) in your unix database and decompress it using UNCOMPRESS utility.
   So you have a file on your unix called Rom8.pcf
2. Create directory in your exceed_directory/font and call it anything you want (example I will use will be "extra").
   So I created directory exceed/font/extra
3. Transfer uncompressed font file into the directory we just created using ftp in BINARY format.
   So you have a file exceed/font/extra/rom8.pcf
4. Open xconfig and go to Font.
5. Click on Compile Fonts.
6. Find your exceed/font/extra directory in the directory tree and select List Files of Type: as *.PCF. You will see your rom8.pcf file and will be able to select it.
7. Click on compile.
   You should get Font Compiling Progress screen and there should be no errors/warnings. It will also say where it put the compiled font file.
8. Now if you go to the directory where the file is, you can move it to your extra directory and remove .pcf file.
9. Go to xconfig and double click on fonts icon.
10. Click on ADD button.
11. Click on browse and find your extra directory.
12. Give it a name that you would like to be shown in the font database.
13. Make sure that Directory selected and Status set to Keep.
14. Click on OK.
15. Click on Rebuild Database and click on Done.

By now you should be able to see your extra directory in your font directories list and if you double click on it you should be able to see your font (both Physical and Logical names). As a last test try to double click on the font itself. It should show you the letters that this font will use.

You do not have to create directory for font that you are installing, you can just copy compiled font to the one of default directories and rebuild database. It will work as well.

If your fonts are in the different format then BDF or PCF (just look on extension of font files), then you will have to translate them into one of those formats using unix utilities.