Wear the right socks. If you wear a thick pair of white crew socks when trying on a dress shoe, you’ll only buy a pair that’s too big.
Get sized. By a professional, using the indispensable Brannock Device, and taking into consideration your foot width. Your shoe size can change over the course of your life, so it’s always best to be accurate.
Buy in the afternoon. Feet can swell throughout the day, so it’s best to try on shoes later in the day when your feet are at their largest.
Check the inside. Check the inside of the shoe, soft lining is more comfortable than exposed grain of leather. Check the insole if it is comfortable and soft.
Check the fitting. The easiest way to tell if a shoe is too big or too small is to take a look at how much room there is in the toe of the shoe. Generally speaking, there should be about one finger’s width of space between your longest toe and the end of the shoe.
Fit the shoes to the larger of your feet. Many of us have one foot that is slightly bigger, so choose the shoe size that is the best fit for this foot. Try the shoes on both feet, even if the shoe snugly fits the bigger foot, make sure it’s just as comfortable on your smaller foot.
Walk around the store when trying them on. Don’t settle for sitting down and checking the tips of your toes; you need to see how they function with your arch flattened and while exerting yourself. Check if any part of shoe is pressing or rubbing against the foot.
Try multiple sizes. Wear multiple sizes and feel the shoes. Check which one is fitting you the best. Same size in different designs fit differently. Similarly same size from different brands may have different measurements.