Re: Taking down your mainsail
Best advice I can give is to try to do it with no wind around. Pull the sail all the way out and then I take a wrap around the winch and lock the halyard into the self tail of the winch.
I start slowly letting out some of the halyard and have an assistant help me flake the sail back and forth from one side of the boom to the other. I try to keep the flakes about a width of two to three feet and just take my time and ease the sail down working the flakes back and forth keeping things as neat as I can until I'm done. Then we set the sail out on an area of flat ground and tidy things up pulling any wrinkles out of the flakes and fold the sail up and put it in the bag.
Do you have a loft where you plan to take the sail to have it inspected for wear and repaired if need be and then shipped off to be cleaned?
I usually wrap a piece of strapping material around the foil about 5 to 6' above the boom and pull that tight and secure it around the outside of the mast to keep the foil from slapping and banging inside the mast while the sail is removed from the boat.