How to Measure for a Collar:
A)Use a collar measuring tool or two carpenter’s squares (L shaped rulers) or L shaped cardboard cutouts. Overlap the long sides of the two rulers or cutouts forming what looks like a letter C or half of a collar. Place that on the animal as if it were one side of the collar. Place it just where you want the collar to sit on the animal. Remove it carefully so the two parts do not slip and measure from the top to the bottom on the inside. That will be your collar size.
B)Look at the front of your horse’s neck. That will determine the shape (sweeny) for the collar. Average, straight necks, i.e. thoroughbred, standardbred are FULL FACE. Necks that are wider at the bottom than the top, i.e. quarter horse, fjord, halflinger, average drafts are HALF SWEENY. Necks that are thick all the way up are FULL SWEENY.