How do you measure head circumference?

To measure head circumference, use a flexible measuring tape and wrap it around the widest part of the head, typically just above the eyebrows and ears, and around the back of the head. Ensure the tape is snug but not too tight, and record the measurement where the tape meets. It's important to take the measurement in centimeters for accuracy. For consistency, it can be helpful to measure multiple times and average the results.