Sand off the shine on the buckets. They come pretty protected, so using light sandpaper, you can prep them for the toilet bowl cleaner. 

Wearing gloves, douse the buckets with toilet bowl cleaner. I held my bucket over a large plastic tub and covered it with the solution. *I let mine sit on its side in the bucket, next time I won't do that because one side became more distressed than the other side. 

Let the bucket sit for 12 hours, then reapply the solution, and let it sit for another 12 hours. 

Rinse the bucket with water, set aside to dry, and flush the excess toilet bowl cleaner from the plastic tub. 

Have fun filling and decorating with your new distressed galvanized buckets!