- 1). Wrap a piece of string around the finger for the intended ring. Mark the place on the string where it overlaps using the marker. The string should be loose enough to move over the knuckle.
- 2). Lay the string flat and measure it with a ruler. The circumference of your finger in millimeters determines your ring size.
- 3). Repeat the measuring process several times for accuracy.
- 4). Look over the ring chart in the reference section to determine your ring size based on millimeters.
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