Abbreviations: k: knit, p: purl, co: cast-on, st: stitch
co any number of sts. I co 15 sts.
Row 1: k all sts
Row 2: p all sts
Row 3: k all sts
Row 4: k all sts
Repeat rows 1-4 until desired length is reached. This swatch is made up of 3 repeats.