To ensure the best fit, measure both feet and use the longer measurement, preferably at the end of the day when your feet may be slightly larger. Wear the socks you plan to use with the shoes while measuring for the most accurate result. If you are between sizes, check the product-specific sizing notes or consider choosing the larger size for added comfort. Keep in mind that sizing may vary between different brands and shoe styles, especially for boots, sandals, clogs, and sneakers.