I would imagine the folds are just pleats, like with a skirt.  You would have to pin the pleats before sewing the back and front together.  For fabric, I'm guessing any stretchy material would be easiest to work with (for me).  Jersey that isn't too slinky/slippery would keep the pleats from sagging in the middle of the front of the dress.

Thanks for the great ideas guys!

I just had fun making a dress from no pattern.  I now want to trace out my dress pieces with added seam allowance onto a nice material that will store well.  What have you used in the past?  (My longest pattern piece goes from my shoulder to my knees).  Right now I can only think of using a good quality wrapping paper.

I'd say it took me about 5 hours to make the New Look 6429 wrap dress.  This time includes cutting out the pattern, pinning it to the material, cutting the material, pinning material together before sewing, trying to understand directions, sewing, and ironing seems when necessary.  It does not include wandering around fabric stores to pick out the best fabric .

I don't know how to make things go quicker.  I usually work straight through a project because I'm so excited to see what it turns out to look like.

Thanks guys .  My ties can be tied on the side or in the back.  They are attached to the dress via the side seems.  I agree Kitschy, the belt is what caught my eye on this dress.  It's a really comfortable dress, being made out of jersey, and it sort of feels like the belt is holding your stomach in.  I definitely recommend a lightweight or slinky jersey. I can't wait to go shopping and get new fabric for it, oh and for spring to come to NYC so I can wear it.

Love the whale sweater!  Looks so classic.

Here is my unhemmed mock-up.  These colors are horrible on me, so I think I'll use different ones in a lighter weight material for the real one (it looks too bulky in the front).  My dress is faux wrap dress.  I think I'll also make the sash thinner so I can not have it highlight my paunch.  The dog can't take her eyes off of it.

I just watched this episode last night and loved it too.  Maybe we should start a sew-a-long thread on it.  Can you post your pictures when complete Squirrelly?

I was going to attempt to make it by altering a pattern for a wrap that turned out successful for me, New Look 6429. 

Do a search on craftster or google for duct tape dress forms or paper tape dress forms.

Dyabolica,  do you have images of your vintage shirtdress and wrap patterns?  You sound like you have an amazing collection of patterns.