Leave broad bean pods on the plant to fully mature and dry. Leave as many pods in place as seeds desired. Most broad bean varieties have six or more beans in each pod.
Pick the pods once they have dried on the vine and when the beans inside are hard. Bring the picked pods into a warm, dry room and spread them out to finish drying for an additional two weeks.
Split open the pods and remove the broad beans. Check that all the beans are dry to the touch. Spread out any that aren't completely dry and allow them to air-dry for an additional week.
Place the dried broad beans in a jar and screw the lid on. Label the jar with the type of bean and the year collected.
Store the jar in a cool, dry place away from direct light. They can be stored in a refrigerator if desired.