You can't measure, you don't know how, or you just don't want to. That's your prerogative. We've found over the past 4 years that sizing is more of an art than a science, but that a size chart is the only way to get accurate fittings.
Why measure your foot when you can simply click HERE and be taken to a magical place where you get what you want with out doing the hard work. Only problem is that the information you are about to get is not really helpful in teaching you the proper way to measure your foot and get an accurate fit. Instead it merely make gross observations and puts them into categories whose information can't be trusted as much as actually measuring your feet.