When you have a good idea on how you want your script to look, things may be easy, but having a good idea may not be enough. You can learn to sing by yourself, but that will not assure you a job at the opera. Same thing with scriptwriting. You have to know at least the basics rules in scriptwriting to make sure that at least the producer will take his time to read your script. For starters, I will tell you about how a producer reads what you might have writen.

FIrst, if it is not written in courier new, size 12, they don't even botther. It's crazy, but that's how things work. Plus, that helps you evaluate how much time the movie will take. One page written in that way means a minute of movie on screen.

Than, they will probably just read the synopsis (that is the subject of the whole movie in just one page). If they like it, they will proceed with reading the first 5 pages, and they expect finding out who the main character is, where the action happens and what is the conflict.

At page 40 they should find the battle betwen good and evil, and in the last two pages the reestablishment of the natural equilibrium. Only if they like it, they will read the whole script and perhaps finance your movie.But at first that's what they do: read the pages from 1 to 5, 40-45 and the last 2.

So, it is a lot of work. It has a lot in common with mathematics.

Since half of the people I know tell me their life is a genuine movie that they would like to make sometime, I will give a few advices on how to make a script

TECHNICAL ADVICES

-never use another tense than present tense in your script. In a movie, you cannot see that someone WENT to a shop. On the screen, the character is a the shop right now.

-you can only use active verbs. That means you cannot show someone thinks of something unless you write on his forehead or something. Cannot say the character wants something. You can only say he/she is doing something.

-try not to write the lines two long. This works perfectly in theatre dramas, but in a movie it might be aquard to have a character that speaks to much. Think about presenting what a character wants to say in an image. For exemple, the character could say hello, but he could also knod his head as a hello. Or he could say: I am angry. And that would sound stupid. Instead he could do something to show he is angry.

-never be ambiguous. If you write "she is crying her heart out" you might have the surprise of having a director crazy enough to make the actress literaly cry her heart out. And you probably wouldn't like that. Think about how laws are made. Hard to interpret and twist.

-Billy Wilder said this: if someone is talking about fried eggs it's not interesting. But if someone is talking about fried eggs and there is a bomb about to explode under the table, the conversation starts to be interesting.

-there is only one main character in any movie. And that is the character that takes attitude. We are in a room and we hear an explosion. The one that goes check is the main character. If more people go check, the one that takes the decision to solve the problem is the main character. If more people take the decision...so on. You probably got the idea.

-sometimes real situations may seem unreal, so it might not be the best thing to do using them. For example if I tell you I found out my boyfriend is actualy my step-brother from my father's affair, you will probably say "Gee, what were the odds". If you feel that "what were the odds" too many times in the same script than you won't believe a thing I say. And that is not good for a movie. So a script doesn't have to necessarly be real, but realistic.

-use the main structure for the script: everything works ok. The situation is in perfect balance. Something happens and ruins the balance. The main character takes the decision of making things right again. He battles the evil and reestablish the balance. Evil could mean there is another character that oposes to the protagonist (like in alien) or a problem (for example in Ikiru, the disease of the main character).

Well, of course these are just a few rules to be broken. For more, you could read Syd Field's Scriptwriting. He makes things clear for beginners.