The main task of a GM is to control the plot. There are many ways to go about this but we will be focusing on character interaction because, let's face it, it's what I like the best and you can't get away from it in any RP even when you are not the GM.
The reason character interaction is so important is very simple. Obviously, there are characters that you control (NPCs) and characters that other people control (PCs). For the simplification of this lesson we will not be considering the difference between PCs and NPCs controled by the GM and we will lump them all together as NPCs. So, you have two types of characters, the types you can control and predict (NPCs) and the ones you cannot (PCs). In terms of the 'plot,' however, every character effects it according to the same equation:
Character Interaction = relationships = unknown variables/known catalysts = subplots.
Character subplots means that no matter what sort of plot you start out with for your RP, it WILL get more complicated and/or change as you go along. So, if your job is to control the plot, but you cannot control all of the subplots that affect the plot, then what are you supposed to do about it?
The first thing you do is deal with it. I have never seen an RP succeed where every character was outlined by the GM from the beginning. People don't want to join, or suddenly they are scared about what they can or cannot do. You just have to sharpen your tools and deal with the fact that your little RP plant is going to grow towards the light or die a painful death.
The second thing you do is take a look at what makes up this mysterious thing called a plot. In very simple terms, every plot looks like this:
Main Plot: setting + circumstance => premise
premise (+action) => conflict
conflict +action => consequences (this step is usually the climax)
consequences (+action) => resolution.
You'll notice that two steps have action in parenthasis. That's because action here is optional. It can act as a sort catalyst in some cases, and in others it can be thought of as necessary to get to the next step. In still others, something a basic as a character's thoughts, facial expressions, or past relationship with another character can serve as the action. What I'm saying is, keep your mind open and keep your eye open for when you can give your players a chance to be a part of an interesting equation.
That sounded corny, but it brings us to our next activity:
Activity
Every RPG needs to start with a premise. There is the larger premise of "OMG the aliens are coming!!!" and then there are the smaller premises that you must use to start a character off. Because I believe firmly is working a**-backwards in creating plot, I've tested the theory of starting with the minor premises and figuring out the rest later. For me, it works. For you, you may want to figure out a single minor premise, such as for a character of yours in the RPG, and then work to figure out the larger premise before starting the RPG. Larger premises do help players choose/create their characters for your RPG.
But at any rate, we are going to start with the smallest premise possible and leave it up to you how big it gets. The first step is to 1. Choose a character profile from the Character Development subforum. Do not choose your own character. The point of doing it this way is to get used to the idea that not every character in the RPG is going to be under your control. You can tell people with a bad profile to please go away, but you can't micro-manage the people with a good profile. If you do not require a profile for your RPG, you will still have to respond to what you learn about the others' characters through the RP itself. When you complete this activity please state clearly near the top of your post in bold or something what character you picked and link to the profile.
2. Choose a setting to start that character off in. Think about what places that character is likely to go. Sometimes you will have a player choose the setting, but this is always in the context of a larger whole that you provide for them. At other times, you will want to start them off at a very specific place in order to hook them into the major plotlines. This first post I like to call a prompt, and usually the more specific and thoughtful your prompt is, the more likely that person will be willing to devote time to the RPG in the future. For this activity you may state the over-all setting in the first line. This is to replace whatever explanation of the RP world you started every one off with. If that doesnt make any sense to you, don't bother with it.
3. Write a prompt! With a setting chosen and a character profile to look at, you should be able to come up with a premise. Why is the character there? Now that they are there, what is there to interest them? Do you want to force them to react to something (for instance, is an alien threatening to chop their head off) or do you want them to notice something more subtle in the environment? Setting the mood is important in a prompt, but please keep in mind that you want some action in this RP, so give the character something to react to. Whatever you do, DO NOT AUTO-PILOT the other character! That character is not yours to play, so set the scene up for them but don't play fortune teller. Even if you feel you know the character pretty well, you cannot predict them 100%.
4. Predict their response. I know, I just told you that you can't do this. Well, you can't, not really, but if you're going to have any sense of control you need to be able to think about what the character might do. Sometimes you will find yourself betting on what the character will do. That's ok as long as you can handle it when you are wrong. Sometimes thinking about it ahead of time helps you write the next post and prepare NPCs and other subplots. So, what I want you to do is write a very simple "prediction" in white text underneath your prompt. It's important that you hide it in white text for the next activity. Here is the code:
[color=white]text[[/color]
5. Compare Predictions. If you can get some one else to take the same character profile and predict that character's response, then the two of you can compare your predictions! Fun!