You've got three options, really: 1) Wear the suit on the plane. 2) Use a suitcase with a foldout suit sleeve/compartment and/or a garment bag with such. 3) Fold the suit inside out and place it in a normal suitcase along with your other items. Choice #1 is inconvenient for me most of the time, especially on longer flights. Choice #2 is how I usually roll, although minor to moderate wrinkling will still occur. I've attempted Choice #3 per the instructions offered by, if I remember correctly, Esquire or GQ. The bag was searched by the TSA, so the folding and delicacy of packing was rendered moot. I'd say there is no great way to travel and totally avoid any degree of wrinkling. That's why I pack a hand-held steamer with me anytime I'm traveling with a suit or sportcoat or both.