2. It's futile to predict the economy and interest rates (so don't waste time trying)
The U.S. economy is an extraordinarily complex system, with 300 million people acting in their own self-interest and responding to each others' actions, government incentives, and external shocks. And that's before we factor in our increasingly frequent interactions with the rest of the world. Trying to time the market is futile. Set up a financial plan that allocates your assets based on your risk tolerance, so that you can sleep at night.
3. You have plenty of time to identify and recognize exceptional companies
Some would argue that it's still not too late to get in on Wal-Mart, decades after going public. While the company's no longer a monster growth story, it continues to crank out 20% returns on equity year after year. That type of consistent ROE is a huge positive indicator of management's ability to effectively allocate capital. I could tell a similar tale about Microsoft's early growth years, right on down to its still-impressive current return on equity (42%).
Amazon.com (Nasdaq: AMZN), though only 13 years old as a public company, has seen its stock double since its 10th birthday. Of these three, it's the only company still trading at growth-stock valuations. Bulls are hitching their wagon to Amazon.com's ability to expand its role as the premier online retailer, and its upside in the cloud-computing space.
4. Avoid long shots
I've said it before, and I'll say it again. Use companies with proven track records as your baseline. ExxonMobil (NYSE: XOM), IBM (NYSE: IBM), and Procter & Gamble (NYSE: PG)are selling for 9, 11, and 16 times forward earnings, respectively. This is what the market is charging for solid, low-to-moderate-growth companies that dominate (or at least co-dominate) their spaces. Expect to pay more for higher-growth prospects, but make sure the risk-reward trade-off on an unproven company is worth it.
5. Good management is very important; good businesses matter more
6. Be flexible and humble, and learn from mistakes
7. Before you make a purchase, you should be able to explain why you're buying
8. There's always something to worry about.
Always remember, if our worst fears come true, there'll be a heck of a lot more to worry about than some stock market losses. Lynch's parting shot is that investing is more about stomach than brains.
ref: http://www.fool.com/investing/general/2010/05/21/how-peter-lynch-destroyed-the-market.aspx