Hmm, I think you're going to run into a similar situation as what I mentioned on the sleeves. The problem is just how to keep the folds stiff. Sadly all of my personal pattern books I inherited from my grandmother, and these weren't that popular in the 50's i suppose

I would start at the waist working in back loops and then about where you need to have the bottom of the first crease, work the front loops for one row, increase your stitches even over the next few rows till you reach the top and do another row...maybe 2 of working in the front loops for the top.
Sorry if this isn't very helpful >.< I'd normally try a piece out for myself so I can see if it will work, but this is what I would try to do when attempting to create them. Maybe after I finish my craft swap project I'll try my hand at it to see how my results come out, but imagine you'll want to start working on this before than. Good luck!
