How to know when your Sunflowers are ready for picking?

Firstly these flowers should be pollinated, either self pollinated or by bees usually bees visit so it's no problem. If not, wait till the head of the sunflower has more volume.
The sunflower's appearance:

Stalk it is connected to must turn yellowish and dry
The petals must droop and dry out (or fall out)
The flower must be heavier and more cup shaped.
It should droop down more, looking heavy
AFTER CUTTING: after cutting the heads, do not pick the seed, wait for a few days for the seeds to plumpen up and dry. You will notice the changes if you observe it day by day. The seeds will be more visible as the flowers separate from each other in the center.

As you can see, this is what it looks like when you pick the tips of the flowers, the black seed is shown. It is still cool you just know it is moist. When it dries out you'll notice white lines appear. But I still planted it even if the seeds weren't totally dried out.

What is important is it is PLUMP!🌻🌻🌻

This is how you know. Actually I could snip these already but maybe tomorrow. My sunflower plant still has a few more flowers blooming I don't know if it will die once it runs out of flowers.