Seed Starting 101

Well, what we'll do first is mix some of our starting mix with water.  I use a small rectangular plastic storage bin to do this.  I usually make more than I think I will need.  Generally, you probably don't want to fill it more than about half full of dry soilless mix.  Then I sprinkle the mix with water and mix it with a trowel.  Add more water and mix, repeating the process until the mix is moist but not sopping. 
Now, we need to fill the trays.  I usually put the tray on a sheet of plastic so I can reuse the mix that I spill as I fill the cells.  Using a plastic party cup, scoop  the mix onto the trays.  I use a plastic ruler to spread the mix over the entire surface of the tray.  You really don't want to press the mix down into the cells, but kinda of let it fall in.  Repeat the process until all the cells are full to the top.  Move the tray to the water pan now.
The next step is actually placing the seeds.  Open ONE of your packets and pour the seeds onto a clean paper plate.  I use a tooth pick moistened in water to pick up seeds one at a time.  Pick up a seed by laying the flat of the toothpick on a seed.  It will stick.  Place it on top of the mix in the center of the cell.  Work down each column and across each row until you are out of seed.  Don't forget to mark that section of the tray with the date and variety.  Repeat the process with the other varieties.  When all the seeds are placed, one per cell, take your toothpick and gently poke the seed a quarter inch down into the mix.  When all are poked in, take a bit more mix and cover each seed.  GENTLY, just touch the surface to firm it, without really pressing down.  Cut the clear cover on the tray.  Continue with any additional trays. 
Keep your trays in a warm location, and check daily to make sure the mix isn't drying out.  When watering your trays, add water to the water pan and not to the surface of the mix.  No more than 1/2 inch of water should be in the pan at any specific time.  Keep watching and after a week you should see the baby tomato plants Poking up.  As SOON as you see the first one, remove the clear top and get them into the brightest light you can.  Preferably, under a 4 foot fluorescent shop light.  (These are available for $10 or so at the local big box hardware store).  If you use the shop light hang it so you can adjust the height.  Keep the bulbs about 2 inches above the top of the plants an raise it as they grow.
That's it for now.  Don't forget to keep an eye on them.  Don't let them dry out and don't let them sit in water.  Remember that they will use more water as they get bigger. 
Feel free to ask any questions.  I'd love to read any comments you might like to pass along.