Store seeds in a cool, dry place away from sun. If your seeds are already dried well, you can store them in plastic zip bags.
If they need to be dried better, store them in paper lunch bags. I learned from a seed seller that she dries bags of seeds in her car. Sometimes I leave them out on a tray to dry. Be careful to cover them in some way that allows air flow but won't let the wind take them away. I use a sifter atop of mine.
Once dried, store them in photo storage boxes and alphabetize them. Be sure and place your collection date on them.