Derivatives are financial weapons of mass destruction. - Warren Buffett

An idiot with a plan can beat a genius without a plan.

But now for the final exam: If you expect to be a net saver during the next five years, should you hope for a higher or lower stock market during that period? Many investors get this one wrong. Even though they are going to be net buyers of stocks for many years to come, they are elated when stock prices rise and depressed when they fall. In effect, they rejoice because prices have risen for the "hamburgers" they will soon be buying. This reaction makes no sense. Only those who will be sellers of equities in the near future should be happy at seeing stocks rise. Prospective purchasers should much prefer sinking prices.

If you are investing in your education and you are learning, you should do that as early as you possibly can, because then it will have time to compound over the longest period.

And that the things you do learn and invest in should be knowledge that is cumulative, so that the knowledge builds on itself.

So instead of learning something that might become obsolete tomorrow, like some particular type of software [that no one even uses two years later], choose things that will make you smarter in 10 or 20 years.