Any nice contrasting colors will do. Black and White, light purple and dark purple. Light pink and dark pink. Really depends on what colors you like or what you are trying to match. The larger size needles allow this to be a cowl neck warmer. I used a wool mix to keep me warm. I knitted flat and then applied Velcro with a small stitch to keep it on. This way I can wear the cowl reversible.
smaller needles different result, like a bookmark.