Here are some drawings..
send the sail down the hatch, if it's a large sail, or simply keep it at your feet if its a small sail...
Pick up the tack end and with both hands start rolling the sail along the luff.
Remeber that as you roll the sail, one hand keeps holding the roll at the tack portion as you rotate the roll (the roll rotates). Not pull the sail around..rotate the roll.
Keep rotataing the roll slowly holding each turn, so the whole luff is in one of your hands..
keep doing till you have the head of the sail in your hand
Once you d, pull the roll out, and lay it on the floor deck or whatever you are..you can also do this inside if its wet outside.
the beauty is it will never fold in the same spot, which is good for the sails.
I do this with my main sail, and that is one big sucker..