Excerpted from The Handbook of Sailing
It is important to know how to ease the tension of a sheet or halyard on a winch. The tail of the line is taken off the cleat but the tension must still be kept on it. One hand should then be placed on the turn of the line around the winch barrel and the heel of the hand used to feed the line around the barrel, as the other hand eases the tension on the line. It is most important that the fingers are kept well out of the way.
For more hints and tips on sailing techniques for both the beginner and experienced sailor, purchase Bob Bond’s The Handbook of Sailing from Practical Sailor.