an analogy for holding too much baggage inside. when the repression suitcase has too many "clothes" inside it or stress, the suitcase will burst. it's important to unload your repression suitcase in an orderly manner to you don't break under the pressure of your trauma.
friend 1: man I feel really overwhelmed and I don't know why.
friend 2: have you unpacked your repression suitcase lately?
friend 1: oh good point.
At a ski resort, it’s a way of using your pole straps to carry your skis by putting your straps around each end of the skis, to carry them sideways by holding the poles next to you like a suitcase, common with tourists that don’t ski often. The normal way to carry skis is over your shoulder upright, so you don’t hit anyone with them.