Roll your items, do not fold.
Keep in mind cottons will crease more than man-made materials when packing.
Make sure you take a variety of layers. One tank, one tee, one light sweater, etc.
Cut down on items by only packing solid colors. These are easier to mix and match and therefore you wont need as many items.
RE locks: Locking your case? Make sure you lock is TSA compatible so they can open it if they must. These days, it is common to cut off any lock that they cannot search.
REMOVE OLD CLAIM CHECKS
Don’t hesitate to ship something ahead of time or back home. Don’t haul around needless items, if you accidentally brought them!