Not a loom knitting pattern but great inspiration! Twenty Something Granny: Knitted Baby Bow Hat. Looks like the bow piece needs to be a little bigger so it's fuller on the finished hat, but this is so adorable!
How to Knit the 3 Color Linen Stitch with Free Written Pattern and Video Tutorial by Studio Knit. via @StudioKnit
Start with 3 colors. Each block is 9 stitches so for however wide you want the blanket, count in 9 to get your foundation (always make it an uneven number of "blocks) eg: 19 blocks(makes it about long) stitches then add 4 sc for the foundation row.