Cut Longer Facings for Better-Looking Garments
When a garment has a separate front facing, such as a blouse, jacket, or skirt, cut the facing about 2-in. longer at the hem. This helps assure a smooth ripple-free application.
Here, the garment front and facing were cut from the fashion fabric.
I recommend using a knitted or woven preshrunk interfacing. It doesn't hurt to preshrink and usually helps the look of the finished garment. But beware, even if you did preshrink the interfacing, it could shrink more during pressing.