All supplies but the laundry machine and laundry detergent.
Soak shoe in water and put some dish soap on it. Scrub as much of the shoe as possible. Note: Remove laces completely to avoid fraying.
Next, soak a cotton ball in nail polish remover and apply to the spots that you couldn't scrub out.
This is especially useful on the lighter colored leather. Scrubbed with nail polish on the left. Only scrubbed with dish soap on the right.
Remove insoles from shoes and put shoes and insoles into pillow case.
Tie a knot in the pillow case and insert into laundry machine. Add detergent and set for a long cycle with cool water.
After wash, put your shoes out in the sun to dry. Congratulations, you just cleaned your Sperrys.
With your newly cleaned Sperrys you may want to add some mink oil to protect the leather.