Roll the bike slowly, inspecting the tire as you go. If this is not possible, place the bike on its side stand, and push the bike so that most of the weight of the bike is on the stand. You can then roll the affected tire, looking for objects. Once you find the offending object, as long as it is not in the side wall of the tire, you should be able to repair the damage. Sidewall damage is NOT recommended for repair.
Damaged sidewalls can lead to blowouts.
Do not pull it all the way out, as you may lose the point in which your tire has been damaged. Now we get into different methods to repair the tire. There are several methods available, but I will cover using the plug kit, the quickest way to get you back on the road safely and into a repair shop. The plug kit c onsists of a reamer, a plunger and some gooey rubber stuff. The reamer is not pictured, but looks much like the plunger, pictured on the right.