How do I create menu link icons?
You can use menu icons module to generate icon for the menu item.


  This module allows you to upload an image in the menu-item's
  configuration form.
  
  After uploading the image, the icon data will be added to the menu
  link's options array.
  
  When a menu link is goes through the theme layer, it will receive an
  extra class which by default is used to attach the images as a
  background image to the corresponding menu item.