Knitting is a mystery to me. Someone recently explained the brioche effect in knitting to me, and if I understood correctly, this technique that I recalled from a pattern I downloaded long ago approximates the effect.

Yarn recommendations, hook size, and gauge are purely arbitrary. Use what works for you.

Yarn: Two solid colors of worsted or DK weight yarn. Could work if one of the yarns is variegated or self-striping, but that has not been tested. The amount of yarn required will vary depending on the size desired and the yarn and hook used.
Hook: Hook size recommended for the yarn. For a looser, drapier effect, use a hook larger than recommended.