[header] How to make a horse blanket [title] Measure the length of the horse. [step] Put the tape measure in the middle of the horse's chest, then wrap it around the side of the horse, over the largest bulge in the shoulder. Measure to the base of the tail, or where the tail and the horse's butt connect. 
Make a note of the measurement on a piece of paper. [substeps] If your tape measure isn't long enough, you can pull a piece of yarn from the chest to the tail, then measure the piece of yarn.