I'm not going to have a recipe for you, DL.
The timing for harvesting the plants is like with the millet, if I'm using it for seed: The finches and chickadees will let me know.
They will start pulling the outside seeds from the sunflowers. Those are ripening first. It is a good idea to have them someplace that the birds can't get at them after they are cut but they probably only need to stay there for 2 or 3 days in your dry climate.
(If I see that the finches are eating the millet - I've got less than a week before they will take every seed.)
Hardware cloth screen (1/2") might be a good way to get the sunflower seeds off the heads but I haven't done that. Gloves work fine.
Steve