sweet pea seeds

I usually collect the sweetpea pods and dry them off on a tray in the greenhouse...then "pop" them when they're dry, and store the seeds in paper envelopes :)

i wait till they are half dry then remove them and collect the seeds when dry. the seeds will have had time to fully form then.

I'd leave them to at least partially dry off then follows SBG's advice

Allow the flowers to age, fade and drop on their own.
Where the blossom was attached to the vine, a stringbean-like pod will form to encase the seeds.
The pod will first appear as a bright, medium shade of green. As the pod matures, it will "puff" with the growth of the seeds.
The color of the pod will phase to a dull yellow-green and when the seeds are fully mature, the pod will turn light brown. (About the color of a paper bag.)
At this light brown stage, they may be pinched from the plant. Place the pods on a plate and allow them to dry indoors for several days. (Adjust timeframe for the humidity in your own environment.)
The pods will begin to split open at their seams as they dry. You can encourage the pod to open by running the edge of your fingernail along the pod seam, then spread the pod open with your fingers to reveal the seeds.
Gently push the seeds out of the pod and back onto the plate. Allow them to dry on the plate for a few more days.
Store the harvested seeds in a paper packet or envelope until you are ready to plant them.