1. Wrap a piece of string or paper strip around the base of your finger.
2. Mark the string or paper where it overlaps to form a complete circle.
3. Measure the length of the section of string or paper where it overlaps around the finger.
4. Compare your measurement with this chart to determine your ring size.
Please note that the best and most accurate way to determine a ring-size is to have it done by a jeweler using a special tool specifically designed for this task.