#8 There's a lot of good resources out there, and there's a lot of not-so-good resources that want to sell you a particular fund/stock. If you are just looking for good return on investment for your personal finances, it's easiest to skip all the theoretical junk and do what works for most investors: put your money in a fund like the S&P 500. Or you could open an account with Vanguard (or a similar NO-FEE investment manager - more on that below) and stick the funds in a diverse portfolio. Vanguard doesn't let you dick around with individual stocks, and for good reason - there's no evidence to suggest that the average investor actually makes extra money by buying/selling individual stocks. On the contrary, people's biases tend to lose them money because they like to sell stocks that have made some money, and hold on to stocks that are in the red on paper "until they turn around" and make a profit. Obviously, stocks that have gone down from where you bought them are no more likely than stocks that have gone up to make you any more money - in fact, they may be more likely to continue to lose.
Don't choose mutual funds that charge fees. The evidence here is actually very clear: mutual fund and hedge fund managers, despite their intelligence, are no better than monkeys at picking stocks to outperform the market - at least, when you look at a long enough time period. If a fund charges high management fees, then you're taking your 50% chance to beat the market and reducing it by the amount of the fees!