I always tell my students to choose a method and stick to it. For main paragraphs, I teach them two easy ways to organise their ideas:
- Idea, explain, example: If you have one main idea, this easy format will help you to build a good paragraph. To see an example, look at paragraph 3 in this essay.
- Firstly, secondly, finally: If you have two or three ideas, just use this format. Miss the "finally" if you only have two ideas, and remember that you can use alternative words for the same structure (e.g. The main reason, another reason, also, furthermore). Click here and here to see examples.