Short of patching, plugging a flat tire is the next best solution, especially if it is a small puncture hole from a nail or screw. Plugs can be installed without removing the tire, making them the quickest, easiest fix. Your plug kit should have two T-handles, one with an eye and one without. To plug the tire, insert the T-handle without the eye into the hole and push it in and out a couple of times. Then, thread the plug material through the eye on the other T-handle, push the T-handle eye into the hole in the tire where you can no longer see the plug and pull it back out, tightly filling the puncture hole. Trim off the loose ends and you're ready to air up the tire and go on your way. One note: Make sure the plug kit you buy is advertised as permanent. Some are designed to be temporary and the repair has limited durability.