1) Whenever possible, print in 'Times New Roman' font. You'll get 100 more pages out of a cartridge than you will printing in heavier fonts like Arial or Verdana!
2) When your computer warns you that your ink is almost empty, take out the cartridge and shake it vigorously a few times--there is still plenty of ink left in there!
3) If your ink cartridge has a reset button/hole, use it when the low ink warning comes on and again, you will greatly extend the life of your cartridge.