I made this scarf with leftover yarn from other projects. A great way to use up a stash of small amounts of yarn. The only thing that I would recommend is that the yarns be of similar weight, and that they are colors that play well together. Other than that, the possibilities are infinite.
The yarns I used were all worsted weight, but they were all of different textures, which adds interest. I made the scarf in garter stitch, so it really couldn't be easier.
Different yarn textures give the scarf interest.