Let the seed head, which is the brown center of the flower, dry completely and become brittle before cutting if off the stem. Then over a paper towel or a bowl roll the seed head between your thumb and finger to dislodge the seeds. You can also put it in a small paper bag and shake them loose.
I think they are sooooooooooooooo picky and hard to get the seeds off of. Maybe I am not leaving them long enough....I think it is hard and was wondering if using something to pound on it would ruin the seed? Good luck and I hope they don't pick you too much margie...