Garments that are stuffed tightly in suitcases are far more likely to wrinkle and crease than garments that have a bit of room to move. When packing your dress shirts, try not to cram too many items in the suitcase with them. However, don't pack too minimally either. If there's enough space for the shirt to bounce and fall around during transit, it will end up wrinkled.
The way you fold your dress shirt will depend on the size of your suitcase, and selecting the right folding method for your suitcase will keep your shirts looking fresh. For large suitcases with a flat bottom, simply pack your dress shirts at the very bottom with the sleeves folded across the front. For smaller bags, such as carry-ons, consider placing a few magazines or a book inside a buttoned dress shirt and then folding the sleeves and hem around the items. This will help the shirt retain its shape in transit.
If you have enough room in your bag, consider packing your dress shirts in shirt boxes. Fold them as usual, and then place them in the boxes. You can use tissue paper to help pad them so they don't bounce around in the boxes. Using this method, your shirts should arrive at your destination looking brand new and free of wrinkles.
As an alternative to packing your dress shirts away in your luggage, consider using a garment bag and transporting them as a carry-on item. Garment bags usually have a plastic lining that reduces friction and minimizes static cling and wrinkling, so dress shirts should arrive in good shape. However, the garment bag could get messed up in the overhead bin on-board. Arrive at the gate early and ask if you can hang your bag with the flight crew uniforms during the flight. If you're polite, the airline staff may allow this as long as there's room and they aren't overwhelmed with similar requests.
