There are a few things I'll do for planning. First of all: Set up the background story. Background stories can help you develop the character and add variety. So your character will no longer be just a man sitting in front of a table and talking, which might lead to your clip looking like a student work and being boring. It doesn't need to be super detailed, nor does it necessarily need to be super simple. The trick is to pick a story which can be told in no more than 3 sentence. If you catch yourself needing a paragraph to explain it, then it's probably too complicated.
Let's say we have an angry guy saying "get out of my house", we already set up he is an angry guy, now there are still a million different ways for him to say it. Is he mad at the person he is talking to? Or is he mad at himself? Is he talking to his son? Or just a choppy boy scout who's trying to help him cross the street (sound familiar?)? These background stories will determine how he is going to deliver his line, and what the suitable acting choices can be as well.
After the background story is set, then it's time to develop the acting choices. There is a nice trick I learned from my acting class, which is very hard, but very helpful. Try to make 12 different choices, and they all need to support the story we set earlier. For myself as an example, I usually find my first 3 or 4 takes are really generic, and the last few are more unique and interesting.
If you have time, go vote at the 11 second club. You'll be surprised at how many of the same acting choices and gestures are chosen. Then you'll know the literal meaning of cliché, and feel its power to make your shot less interesting and more ordinary.
Article created by Erik Lee, refined by Joseph Taylor.