I thought I would share how I pack my dress shirts into a Packing cube so they won't wrinkle.
I have used this with great success for quite a while and find it works much better than a packing folder, also much lighter. The air trapped in the ziplock bag prevents wrinkles while the socks in the collar prevents the collar from collapsing and creasing. In my entire time traveling like this I have never had to iron a shirt and have actually been accused of buying a new shirt upon arrival because it looked a bit too crisp for a packed shirt!
For this I use the packing cube backpack, a thin plastic cutting board from the dollar store that I cut a little smaller than the packing cube, a large ziplock bag at least an inch bigger than the cutting board, a pair of socks (thin undershirts and underwear also work well) and of course the shirt.
Step 1. Lay shirt front side down on a flat surface making sure buttons are going down center and place cutting board on back, making sure collar is entirely on the front face of shirt.
Step 2. Using cutting board as a guide fold in side of shirt then fold in sleeve. Try to minimize folds here, one is usually enough. Repeat for next side.
Step 3. Fold shirt over and tuck in tails and cuffs.
Step 4. Insert into ziplock bag, place rolled up socks in collar and seal bag with enough air to pad the shirt but not be too bulky. Place in packing cube.