However, if you don't want your hem to show, you'll need to make use of an underlining. Silk organza is a lovely choice for underlining a full skirt in a fabric with some body.
The horsehair can be attached with the same facing technique as above but catch stitched to the underlining only rather than top-stitched through all layers. This is the technique I used with my yellow dress, which was underlined in a bright yellow silk organza. (I blogged the underlining process here.)
Here's the inside:
And the outside! The horsehair hem is undetectable.
|Basting stitches from the outside|
|Basting stitches on the inside|
One more possibility: if your pattern has a hem facing, you could also nestle the horsehair within the facing.
So many options!
I really like the horsehair that Steinlauf and Stoller stocks (here's the product page). I've noticed a big difference in quality from place to place, and their stuff is the good stuff. Nice and sturdy. You don't want any of that floppy braid! You have to call or e-mail them to place an order. But don't be shy; they're awesome. All their info is on the site.