Seed Harvesting

Liz recently suggested a seed swap in Sept some time. I seem to have a couple of large sunflowers that have not been ripped to pieces in the raised bed, and want to harvest some seeds before the heads are taken (as they were last year).

Question. The seeds in the heads look about ready to harvest for planting next year. The heads are clealy not flowering any more, and the seeds are not dry yet (like you find in a packet if you are buying the seeds). Am I ok to either take the seeds direcly and put them away to dry and store for next year, or take the heads and dry them so as to harvest the seeds?

Any advice on the best way to get seeds most welcome.