Ok, slightly more serious answer – expanding on what @kilyn has already succinctly summarised – with an excerpt from “The Investor’s Manifesto: Preparing for Prosperity, Armageddon, and Everything in Between”* by William J. Bernstein, highlighting by yours truly for your convenience if you’re not inclined to read the entire paragraph:
While I can’t say I agree with Eugene Fama on the full scope of his Efficient Market Hypothesis which earned him the 2013 Nobel Prize in economics (I better like the Irrational Exuberance stuff by one of his peers he shared the prize with, Robert Shiller, but I digress …), but I do agree with the sentiment of his findings in the scope of “trading rules”.
I personally like @CryingSofa’s advice best: find a fixed pattern** towards your goals, stick to it.
* Excellent book, highly recommended if you’re interested in investing.
** No, not on seemingly historic statistical “evidence”.