To gain additional width in shoes that are slightly too narrow, try these modifications:
Note: Try these modifications on a pair of old shoes first. Use extra caution when handling sharp tools.
Shoe liners take up extra volume inside shoes. Try wearing your shoes without the shoe liner.
If you need more room across the forefoot try lacing your shoes 1 or 2 eyelets back. You may also add a small incision below the first eyelet for additional expansion.
Some shoes have stiff material lining the sides of the shoe. Try adding small “gills” to allow for extra expansion.
Some shoes have stiff material lining the top of the toe box. Try adding small rows of slits in the toe box to allow for extra expansion.
To add more room in the toe box, try using a stretching tool such as a ball and ring shoe stretcher.