1.    Be sure the gourd is mature --- hard to the touch.  If it will give any  when you mash on it  --- leave it be.
2.   Use a large knife to scrape the outer layer away.  Scrape hard and thoroughly.  Be sure to scrape the stem as it also has an outer skin as well.
3.    Scrub the peeled gourd  with steel wool using chlorinated water, rinse, set on a board in a cool space.

The gourd would dry in 2 weeks or less.  This is the method to use to get those strikingly clean gourds.