Remove the pedometer from the detachable holster. Remove the battery and the battery holder from the pedometer as well. You want to strip the pedometer down as much as possible.
Fill a small Ziploc bag full of uncooked rice. Put the dead pedometer into the middle of the rice. Seal the bag and let it sit for three, four or more days.
The uncooked rice absorbs the moisture.
After several days, remove the pedometer and add the battery assembly. Hope for the best.
This has been advised for cell phones that have gone through the laundry, so perhaps it will work for the pedometer.
If you have any moisture absorber packs that frequently accompany products, stick those into the bag as well.