Long before they could go to the local garden center and buy seeds in packets, farmers used to save their seed from year to year. In today's garden, it is still possible to do this. Select plants that produce seed in their first year and self-pollinate. Plants such as peppers and tomatoes are good candidates. Because squash plants are cross-pollinated by bees, they require special care to ensure the quality of the seed.
Scoop out the seed from the self-pollinating vegetables once they are ripe.
Pollinate cross-pollinating plants yourself to ensure the best quality seed. To do this, collect pollen from the stamens of desirable squash blossom plants and transfer them to the pistil of the squash blossoms of other plants. Cover the blossoms with a paper bag and close the mouth of the bag around the blossom to prevent it from also being pollinated by bees. Save the squash that is produced and scoop out the seed. This procedure should also be followed with corn, cucumbers and other cross-pollinators.
Put tomato seeds in a glass jar with water and stir daily to allow the coating on the tomatoes to ferment away. Allow tomato seeds to dry on paper towels. Spread pepper seeds on paper towels and allow them to dry. Wait for bean seeds to dry in the shell and pick them out. Allow squash gourds to harden to ensure that seeds are mature. Split the gourd open and scoop out seeds and pulp. Wash the pulp away and place seeds on a paper towel to dry.
Store seeds in glass jars in the refrigerator with a little silica gel to keep seeds dry.