Find your best fit
Measure the widest part of each natural nail from sidewall to sidewall. Record both hands because matching fingers are not always identical.
Method 1: Soft measuring tape
Place a flexible measuring tape across the widest part of the nail and record the width in millimeters.
Method 2: Clear tape + ruler
Place a small strip of clear tape across the nail, mark both sidewalls, remove the tape and measure the distance between the marks in millimeters.
Fit check
The correct press-on should cover the nail from sidewall to sidewall without pinching or overlapping onto skin. If between sizes, choose the slightly larger tip and gently file the sides.
Before you apply
Lay out all ten sizes in order and check the fit again before using tabs or glue.