This pattern is a tutorial on double knitting. Knitting across one row, you’ll create what are actually two pieces of stockinette fabric, with their purl sides against each other. You’re using one color on one side, and the other on the other side. But you’re knitting them at the same time instead of separately.
Although it can become more complex, with most designs in double knitting, the “negative” on one side is the “positive” on the other.
Practicing on this easy scarf will give you the ability to double knit more difficult patterns later.
Choose either two solid contrasting yarns, or one self-striping yarn and one contrasting solid yarn for your first try. This way you can easily distinguish between your two sides as you go.