Before staining, prepare the siding by washing off any dirt, mold or mildew that may have taken hold. Use a household bleach or other cleaner to clean the surface and allow it to completely dry before staining.
Siding can take days to dry thoroughly, depending upon the temperature and humidity level in your area. Plan to wash your siding at a time when nice, dry weather is forecast for at least five days.
Once you have begun staining, you may need additional coats to get the color you like. Allow each coat of stain to dry completely, according to manufacturer's directions, before applying a new coat.