What I've found most challenging with chiffon and georgette is the laying-out process. Sheers are slippery and they tend to crawl about while you are trying to handle them. What I do is use an underlay. I do this by laying the sheer fabric on top of an old sheet or muslin fabric (anything you don't really care about) and cutting them together with a rotary cutter. The sheer fabric clings to the other fabric and makes cutting a lot easier. Also, misting with spray sizing or spray starch has worked for me too!
For my seams, I use a "scant" french seam. I do this by: (1) pinning WRONG sides together. Stitch 3/8" from the edges on the right side of the fabric. (2) Trim seam allowance to 1/16". Fold RIGHT sides together, with stitching line exactly on the fold. Press flat. (3) Stitch 1/8" from fold. This step encases the cut edges. Check the right side to be sure no raveled threads are showing. Press seam to one side.
BTW, this is Simplicity 4112... I'll have finished project pictures later.
I hope this helps those who have not or have been reluctant to sew with a sheer. This is what I do. If some of you more experienced sewers have better methods or something to add, please feel free.