The best way to measure to your foot is to do the following:
Note: in the circumstances that your 2nd toe is substantially bigger than your big toe, then measure to your second toe. If you have one foot bigger than the other, then measure your biggest foot.
Please note for half sizes it is typically best to size up a 1/2 size for women and size down a 1/2 size for men.
Please refer to the chart below to for your size in Archies.
Men's Size Guide
Women's Size Guide