I can recall having read, somewhere, that weighting wet or damp garments while they're line-drying will help to keep out some of the wrinkles. Don't know if this is correct, as I haven't tried it yet but now I think I'll have to give it a whirl, so to speak.

During the 1940's, to the best of my acquired-by-reading knowledge (just so you know, I was reading about victory gardens in particular and rationing in general and this was mentioned as an aside), to save time and, more importantly, electricity (or other fuel if you were using a stove-heated flat iron/sad iron), ladies often placed a hot water bottle over the hook of a clothes hanger and then hung a blouse, buttoned, over the hanger-suspended hot water bottle to work out as many wrinkles as possible overnight. Also saved having to launder the garment quite so often, as it would have to go to a laundry to be done by someone else, or in a Laundromat to be done by the garment's owner if there were no clothes-washing facilities "at home," whether home was a house, a row or townhouse, or an apartment or a duplex. Or, yes, hand-wash it in the sink, but then you're back to where you were: a laundered garment in need of crease-control.
Anyway, just a thought, and I apologize for rambling on.