#1: Before planting your seeds check how long it will take to germinate (sprout) your seeds. Starting plants to soon in the season will result in long leggy plants. Planting warm season plants would be pretty safe to plant in the ground after Memorial day or after the last frost date in your area.
#2: For those who never started seeds the greatest way I feel is to use a tray with soil cells and a plastic top. Place two seeds in each cell. Follow the directions that come with these starter kits. Extras would be to have a warming pad under the tray that holds the soil cells and a florescent light above the tray for the effect of longer sunny days.
#3: As your plants grow transplant into a container the size of a soup can. If you plants get to leggy, transplant these to a larger container. You could use a large pot and place several plants in this container.
#3: Now that your seeds are ready to go out side you must accumulate them to the outdoor light. Planting directly from the tray to the ground will result in burning the leaves and possibly death. You should place those plants in the shade a few hours a day and then bring them back inside. Do this for about 7 days. After the 4th day if the weather at night stays above freezing you could leave these plants outside but beware of the animals also such as chipmunks who love to dig up plants. Keeping your plants close to your house will help keep them warmer at night also.