For the best fit, you can size your own nails or let me size them for you. Self-sizing is usually the most accuarate since you know your nails best. If you'd like me to size them, I will try to keep sizes as accurate as possible, just make sure the photos you send are clear, well-lit, and taken at the right angle. Even the smallest issues such as lighting and blurry details can cause the sizing to be a little off, but I will always do my best with what you provide. Since every set is made especially for you, please double check your photos or measurements so we can make sure your nails fit perfectly.