Some companies (like us) make them bigger for taller guys and smaller for shorter guys. 42" X 42" would be for someone 5'6". 48" X 48" would be for someone 6'. 54"X 54" would be for someone 6'6".

Different makers use different measurements. There IS NO STANDARD when it comes to the size of a Fly Plaid. The sizes I listed above are what we use (or close to it) as they're what we think works best. Each kiltmaker (and "fly plaid maker") will have a differing opinion on it. The truth is: there's no 100% right answer. Cut a square a bit BIGGER than you think you might need, then test it (BEFORE fringing it). If you want it a bit shorter, cut a bit more off each side and re-test. Work your way down until you like the size, then fringe each side 1" to 1.5".