If you are like me, you do more than your share of travel. Business conferences, etc... Lots of places where you ahve to spend a couple days in khakis and collared shirts, and maybe a sport coat. Life is so much easier if you can fit all your stuff into a carry on. Using this technique maximizes space an minimizes (but does not prevent) wrinkles. You may need to touch up with an iron in the hotel room.
Here is how I Pack my carry on suitcase.
Step 1: Lay out your shirts.
Notice that we start outside the suitcase. Lay out your shirts flat as you can, one on top of each other on a flat surface, such as your bed. Button any shirt all the way up and make sure the collar is not folded funny.