Cleaning sails

It's September and the thoughts of sailors turn to: Cleaning sails.

You could take the sail into one of the sail repair houses and pay $1 a square foot or whatever the going rate is nowadays or:
Check for tiny holes and sew them up. Dental floss works well!
Buy a bottle of sail cleaner (ie detergent) and a scrubbing brush.
Spread the sail out on a warehouse floor, take off your shoes and scrub and hose until it is clean.
Then hang it out on the washing line to dry.
That's all that sailmakers ever do. There's no magic to cleaning sails.