A few tips for when you write an outline
Identify your topic. This should be short but still a complete sentence. This will be your anchor throughout the writing process, keeping you on topic.
List your main points. Your main points are the things you want your audience to know after reading your work. All the main points should be a building block towards your thesis.
Structure your argument. This needs to both flow and make sense to your reader. What do they need to understand first? Second? Third? As you get into writing you may need to change the order of your points, this is normal.
Add sub-points. Sub-points go under the main points—makes sense, right? To have a balanced work, the sub-points for each main point should be somewhat equal. If you have seven sub-points for one main point and two for another, it might be time to reconsider your main points as the one with only a couple sub-points may not be a strong enough argument for your overall topic.
Evaluate and adjust as necessary. Read through your outline. Does it flow? Does it make sense? Is it missing anything? Are there gaps in logic? Is there extra stuff?
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