<dir>/usr/X11R6/lib/X11/fonts/TTF/</dir>Newer systems suggest that any local modifications should be put in /etc/fonts/local.conf, as /etc/fonts/fonts.conf is replaced when fontconfig is updated. If you do not have a /etc/fonts/local.conf, simply make the above change in /etc/fonts/fonts.conf. Force fontconfig to update its cache, with.
fc-cache -f
You should also consider uncommenting the section in /etc/fonts/local.conf
that says ``Enable sub-pixel rendering'' so as to get better quality
output. (The end of the comment line is marked by ``->'', so move that
symbol from the end of the section to the end of the line starting ``Enable
sub-pixel rendering.'')