If ordinary soapy water does not shift a mark, baking soda may help. When mixed with water, it forms a paste that can loosen some dirt from suitable surfaces. It is particularly worth trying on white canvas or rubber, provided the material can tolerate gentle abrasion.
What you need: Two tablespoons of baking soda, a little water, a soft toothbrush and a damp cloth.
Mix the baking soda with a small amount of water until it forms a thick paste. Test it on a hidden patch of the shoe first. If the material looks unchanged, gently rub a little paste over the mark. Wipe it away thoroughly with a damp cloth and let the shoe dry naturally.
Avoid vigorous scrubbing. Baking soda can scratch or dull some finishes, so it is best avoided on delicate mesh, suede and surfaces that mark easily. For leather sneakers, use a cleaner intended for that material.
