All you need to do is take paper egg cartons (styrofoam won't work for this purpose) and cut off the lids. Fill each cup with potting soil and add your seeds, placing them at the depth indicated on the seed packet. Place the cups on a shallow tray. Jelly roll pans would work for this, but I use an old plastic boot tray. Then fill the tray with water. The water will soak up through the cups. Cover the trays with plastic wrap and keep in a warm sunny place. When your seedlings are ready for the garden, just cut the cups apart and plant the seedlings (cups and all) right into the garden!
Check out my previous Works for Me Wednesday Posts:
Inexpensive Baby or Bridal Shower Favors
Healthy Oatmeal Chocolate Chip Cookies
Use Up Leftover Hard-Boiled Easter Eggs
Stock Up on Forever Stamps
Thrifty Baking: Tips to Reduce the Cost of Baking
How to Save Money on Organic Foods