Eventually, you have to set it and forget it, and I don't mean only three EASY payments, I mean, of course to say that you decide that's it, my project is done and requires no further tinkering. That's the thing about any kind of art, whether you're doing an oil painting, or creating an icon. How do you decide when it's finished?
Once you have a likable, pleasing product from your efforts, stop fidgeting with it and leave it be. Its easy to mess up a design by over-engineering it, and most editors lack the ever-useful undo option, leaving you to retrace your steps in the case of a boo-boo (technical term). Its also important to remember to both save, and back up your work, though that also applies to any other data you dont want to lose.
You may also wish to take screenshots of your custom icons so that, in the case of data loss, you can go back and re-make them using the screenshots (of the editor window) as a guide, and just plunk in the pixels where needed. Sort of a paint-by-numbers way of doing it.
Naturally, these fundamentals also work for about any other device on the planet, and you may soon find yourself poking around with an icon editor for Windows, or designing icons to paste in the Get Info box on your Mac, or even dig that old Amiga 500 out of the closet just to (re-)explore its venerable IconEdit of years past.
Try it out! Make some new folder icons or change the way your web browsers icon looks just for kicks. Its perfectly harmless and (generally) reversible, so why not give it a shot.
Whatever the case, remember that overall you are designing for you and the icons should be appealing and eye-catching to match your own personal tastes, not to impress the guy down the hall. If they happen to impress him anyway, bonus!
Class dismissed.
