Yep, hanging them up is best. Sometimes Riverkilt's weighted clips are needed.

I get away with using regular skirt hanger but the wider one would be nice. Somebody had the idea of two and folding the whole kilt in half so both hangers hang.

The problem is the pleats are separating near the top and blousing out. Some maintenance may be required. That's why you read about kiltmakers doing that little bit more, or some buyers sewing down the fell (I think that's the right name for the section that's sewn down the pleat from the top). Or steaming and ironing.

There's less work to a heavier kilt that's made right, they just fall into place every time.