A crisply ironed shirt with a collar that stays perfect the entire day can go a long way in giving you a neat and groomed appearance. Nowadays, most shirts have collar stays to hold them up, but a little bit of starch can ensure crisp collars that do not curl under and look sloppy.
Lay the shirt on an ironing board with the inside of the shirt facing up. Spread out the shirt's collar, and spray a quick blast of starch over the entire collar. Iron the collar flat.
Turn over the shirt so that the back of the shirt faces up. Spray the collar with starch, and iron the collar.
Iron the collar until the starch dries.
Fold the collar as it will be folded when you wear the shirt. Iron the area near the fold, about 1/2 inch from the edge.