/etc/fonts/local.conf

<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
<match target="font">
  <edit mode="assign" name="antialias">
   <bool>true</bool>
  </edit>
  <edit mode="assign" name="hinting">
   <bool>true</bool>
  </edit>
  <edit mode="assign" name="hintstyle">
   <const>hintslight</const>
  </edit>
  <!-- try hintmedium if it looks bad -->
  <edit mode="assign" name="lcdfilter">
   <const>lcddefault</const>
  </edit>
  <edit mode="assign" name="rgba">
   <const>rgb</const>
  </edit>
  <!-- set to match your display -->
</match>
</fontconfig>