You can either work this blanket from Karma Cotton, which is a softer cotton version, or from Reborn Wool to make it a warmer and more rustique version. The blanket is worked in garter stitch in 3 super easy steps: First you work a triangle in the main color A, then another triangle against the first one in contrast color B and then you work a 3rd triangle against these two working the first half of stitches in color C and the second half in color A.
Of course you can also work with 4 different colors.