I wear kilts, I sew modern kilts, and knit kilt hose. I don't think your friend would be happy with a knit kilt. If you were to knit a kilt I would suggest knitting a flat piece and then turning it in to a kilt. I do not believe that a knit kilt would have the right swing.
The definitive directions:
and if you want to make a non-tartan Contemporary kilt directions for the X-Kilt (from xmarksthescot.com) Contemporary kilts are made from heavy cotton material, I like heavy no-iron.
Joann's Fabrics will often carry a light weight polyester cloth in Royal Stewart, Black Stewart.
If you friend want a starter kilt look at Stillwater Kilts. Stillwater offers a starter kilt for about $30 (US) in acrylic fabric. These kilts are excellent quality for the price.
A step up in quality there is USAKilts.UsaKilts have a broad cross section of products from off the rack polyester kilts to made to measure polyester and wool kilts, and full kilt packages.
There are a lot of kilt makers and suppliers in the US and world wide these just two I like.
Have your friend stop over at X Marks the Scota forum for kilties.