1, direct comparison method: By directly observing the size of soles and uppers, larger soles or uppers generally occupy more space, while smaller soles or uppers occupy the opposite.
2. Use a ruler or measuring tool: For some soles or uppers whose sizes cannot be directly compared, you can use a ruler or measuring tool to measure them.
3. Use the proportional relationship: By comparing the proportional relationship between the sole and the upper, we can get which one is bigger and which one is smaller.