You will need: lace weight yarn (0.5-1.0 skeins, I used 0.75); size 13 needles
CO (LOOSELY) anywhere from 20-40 stitches
Row 1-7: knit
Row 8: purl
Row 9: knit
Row 10: purl
Row 11: knit
Repeat these 11 rows for the entire length of your scarf. You can alternate stockinette and garter whenever you'd like, I chose to do 7 rows garter and 4 rows of stockinette for the majority of the scarf mixed in with larger and smaller intervals.
At end, BO LOOSELY! Sew both ends together with excess yarn.
Although this could be knit in pure stockinette (as long as you block out the curls), I think the "stripes" that the garter stitch creates adds a nice variability to the scarf. Ravelry page found here.
My scarf turned out to be 5 feet long which sounds like an awful lot, but ends up being quite short. I double wrapped the scarf around my neck and it nicely drapes for 15 inches.