10 Steps to Starting a Garden From Seed
Hardware stores and garden centers sell plastic plug flats, large trays filled with small cells that hold seeds and nutrients, for about $3. You can also make your own planters out of milk cartons, egg boxes, take-out containers, or even rolled up newspaper, or anything that will hold an inch or two of seed-starting mix. Make sure to use a tray underneath to catch moisture.
Once the weather is warm enough to put the plants in the ground, you need to "harden them off." Put the pots outside for a few hours at a time in a shady location shielded from wind. Leave them outside a little longer each day, with increasing amounts of direct sun. In about a week they will be ready for planting in the ground. Plants in peat or newspaper pots can go directly into the ground, but cut out the bottoms so the roots can grow and cut the tops back so moisture isn't wicked away from the plant. Transplant the little guys into prepared soil at the same depth they were in the pot.