Believe it or not, dry cleaning is not the best way to clean your shirts. Yes, you're taking it to professionals, but even the best dry cleaning can lead to your favorite shirt's demise. After all, the process involves an intense chemical bath which can weaken fabric fibers and give white shirts a yellow hue. A better option is to simply machine wash your shirts at home in warm/cold water with a non-bleach detergent like OxiClean and let them air dry. You'll find that the casual shirts like plaids and oxfords won't even need to by ironed. (Dress shirts will likely require a quick pressing.) It's a simpler and more affordable way to keep your clothes clean, which will also prolong the life of your favorite garments.
If you insist on taking your shirts to a cleaner, ask for them to be laundered and hand-pressed with no starch. It may cost a little more, but starch unnaturally stiffens the shirt and shortens its lifespan, while machine-pressing can crack your buttons or flatten your collar. And when you spend your hard-earned dough on clothes you love, don't you want to keep them in the best possible condition for as long as you can?