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The way your wig fits your head is very important. A good comfortable fit is necessary if you would like to wear your wig for an extended amount of time. To measure your head for a wig, use a cloth tape measure that has not been stretched for accuracy.
Forehead to Nape
Start the tape from the centre of the front of your hairline to the hairline at the nape of the neck. If you have little or no hair, lay your index, third, and ring finger flat against your forehead just about at the brow bone. At the top of the three fingers would be a good straight point. Measure until about an inch below the small bone at the bottom of the skull.
Ear to Ear
Lay the end of the tape about a half inch above your little crease (where glasses rest) at the top of your ear between the ear and the head. Bring the tape across the top of your head to meet the other ear, without touching the ear, at the same point.
Circumference
Start the tape at your hairline at the centre of your forehead. Run the tape around, behind the ears, passing your hairline at the nape of the neck, and back up to the middle of your forehead.
Temple to Temple
Start at your temple, and bring the tape measure around the back of your head to reach the other temple.