How does a Lab report for Chemistry look like?

[butterflii]

How does the format look like? Does anyone has an example? I know you need a title, purpose, introduction, procedures, results and discussion, calculations, and conclusions. Do you have to label each paragraph with those names or just type in the information w/o labeling the purpose, introduction, etc.? Also when you type the calculations part, do you type in a paragraph form about what calculation you did or you can show the actual calcuation with number?
So on the procedures part...do I write it in a paragraph format or can I write the step by step using number to indicate the step? For example, 1. Add 20ml of NaOH, 2. Stir it slowly. Which way is better?