Loosen the laces on the boots and open them as much as possible. This allows the sunlight to hit more of the inside of the boot.
Shake baking soda into the boots. You only need a thin layer of baking soda.
Leave baking soda inside of the snowboard boots in a sunny spot, like outside or on a window sill for two to three days. The amount of time it takes for the snowboard boots to dry depends on how wet they are. While the shoes are drying, the baking soda will absorb the foul odors in the snowboard boots.
Vacuum the baking soda out of the boots with the vacuum cleaners attachments. If a smell still lingers, add more baking soda and wait an addition two days. Vacuum out the baking soda again.