Washing your goggles in water regularly will also prolong the life of the goggle foam, sweat will deteriorate foam after a while making it brittle and cause it to crumble and fall apart. Do not throw your goggles in the washing machine as the rough nature of the wash cycle can damage the goggles and some washing detergents can also be too harsh on the lens.
Let your goggles dry in a cool place out of the sun and avoid placing them back in the goggle bag until they are completely dry as trapped moisture can also damage the foam.
If you are having trouble with your goggles continually fogging you may want to use something like “Fog Off” or Scott Anti Fog Spray this is safe to use on your lens and very effective in colder conditions.