When it comes to fund managers and market strategists, this year's hero usually turns into next year's zero.

An index fund is a fund that simply invests in all of the stocks in a market. So, for example, an index fund might invest in every single stock or almost every single stock in the U.S. market, it might invest in every single stock abroad, or it might invest in all of the bonds that are out there. And you can make a perfectly fine investing portfolio that mixes equal parts of all three of those.

You have to understand your own psychology. You have to understand that human beings weren't really designed to invest. We have all these emotions that are appropriate responses if you're being chased by a tiger, but they're terrible responses if you've got a 30-year time horizon to think about investment or when you're trying to manage investment over 30 years.

The purpose of investing is not to simply optimise returns and make yourself rich. The purpose is not to die poor.

It's bad enough that you have to take market risk. Only a fool takes on the additional risk of doing yet more damage by failing to diversify properly with his or her nest egg. Avoid the problem-buy a well-run index fund and own the whole market.

99% of fund managers demonstrate no evidence of skill whatsoever.

You have to understand what market history looks like. What market history tells you is that the very, very best investments are made when things look the worst.