The key to looking as crisp as possible is to do a thorough ironing job on your shirts. In addition to the sleeves and body, an oft-forgotten section of button-down dress shirts is the pleat, centered on the back and between the shoulder blades. Ironing this perfectly flat to the back of the shirt is a small touch that makes you look that much sharper and attuned to the details.
Set your iron to its hottest setting -- usually cotton -- and be sure the steam dial or switch is on.
Lay the shirt back-side up, with the back pleat centered on the wider end of the ironing board.
Adjust the pleat with your fingers to remove any wrinkles. Lay the press cloth over the shirt if it is made of synthetic or a synthetic and cotton blend, as direct heat from the iron may scorch or melt the fabric.
Press the pleat flat, paying attention to the small hanging loop typically stitched above the pleat. Give a small tug to the collar while doing this to keep the pleat straight as needed.