Ever wonder how to go about patching a hole from a nail or hook in your wall? Well for holes up to 3 inches wide, just pick up a Patch Kit like Elmer's Drywall Repair Kit (roughly $19) at your local hardware store. The kit comes complete with a thin wall patch and all the tools necessary, except the paint of course.
Simply position the patch over the hole, apply the joint compound and let dry. Then all you need to do is sand the area smooth, remove the dust with a wet paper towel and finish with a coat of your paint! Voila!