Synopsis, man, that sounds FUN.
Now you have all your main characters. How much farther do you still have to go? It all depends on how quickly you determine the plot. I found a thing online that will help doing it a lot. Somewhere you choose three disasters. Disaster 1 sets the story into motion, disaster 2 begins character development and the character arc(s), and disaster 3 takes place before the grand finale where things take its final turn for the worst and the character looses or regains hope. Something like this would be a major fort is taken in a battle but the war is still not over or when the love rival gets to the boy before the other girl does.
From there, you begin filling in holes and using cause and effect until you get to the point you want. Everything else is fillings and the line that ties point A to point B and Point B to Point C. Maybe you want more disasters, so go ahead and begin doing that. When that's done, wait a couple of days and go back over your outline. Is there anything you want to change or add or even cut? Do this a couple of times before you have a big finish.
It may be a good idea to ask someone else to check it over so you can get some fresh ideas or input, just make sure that they know what the heck's going on in it. An editor would be perfect for those who are looking to make a profession out of it but if you're just starting out or doing it for fun, ask a parent, teacher, or friend that you trust. We need this to make sense.
Now that that's over, you can begin making changes to the story line or just redraft it. Then again, you can just skip over it and begin the rough draft of the story. Keep the outline at hand so you know how things will work out as you go. Now go and be free! Your stories await!
