6) Never, ever work math problems in pen. This one is pretty simple. You will make a mistake; it is only a matter of time. When you do, you will want to completely erase your mistake and write over it. You will never, ever want to scratch something out and write next to the scratch-out. This will lead to a paper that is hard to read, and the scratch-outs will actually increase your anxiety about solving these problems. You want clean-neat paper with a clean well thought-out solution.