Lay your dress centered on top of the skirt.
Cut using the edge of your dress as a guide, leaving room for a seam allowance and perhaps a little extra for growing room if the dress you are using is a little small (that's what I did here)
Sew the 2 pieces together down the sides keeping right sides together. You'll have something that looks like this :
I hemmed next using bias tape. If you've not ever learned the easy way using angry chicken's no swearing bias tape method then hop on over there and you'll be find yourself never hemming anything any other way.... I know I know - usually people hem last, but I am not really much of a rule follower ;)
I love bias tape - seriously - if I wasn't already married I'd be engaged to bias tape.
Cut the straps - I just eye balled it and then shortened them later to the right size when my girl was handy :) I made mine a little wider at one end so that I could gather them a little (I'll explain that in a minute...)
Right sides together, sew along the sides and then turn right side out and press.
Like so :)
I wanted mine gathered at the point where they are sewn on in the front. I just basted, gathered, and sewed again, so keep it all stable for sewing
It's really only a 30 minute adventure to make this sweet dress - and it's sooooo easy !
I love that I get the zipper - without the fuss :)