METHOD 1:

Use a piece of dental floss or a skinny piece of string and wrap it around the middle section of the toe (or thumb, knockle or pinky) where you would like the ring to rest.

Cut or mark at the exact location where the two ends meeet (be careful!) making a complete circle.

Line the floss up against a flat ruler that has a millimeter measurement, and use that number as your 1st size.

Then, measure the widest part of toe pad repeating the process with the floss.  This measurement will be entered as your 2nd size.  For best results, round down, not up. 

For instance, your order will look somethjing like this:

1st size = 44 mm
2nd size = 48 mm

METHOD 2:

Print this page and cut sizer along the lines. Make sure your printer is not reducing or enlarging the sizer. This tool should print at just under 2 1/2 inches. If it prints too large, try reducing the size through the printer settings.