This stitch is known by a few names for this Crochet Simple Texture Scarf. It's called the Moss Stitch or even the Linen Stitch. This is a free pattern available on Yarnspirations featuring Caron Cakes Yarn, exclusive to Michaels.
You will use only 1 ball of Caron Cakes. The colour transitions are as they come out of the ball. So you don't have to fuss about changing yarns in order to get an array of fun colours.