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What should I be aware of as a young investor?
I'm 39 and have been investing since my very early 20's, and the advice I'd like to go back and give myself is the following: 1) Time is your friend. Compounding interest is a powerful force and is probably the most important factor to how much money you are going to wind up with in the end. Save as much as you possibly can as early as you can. You have to run twice as hard to catch up if you start late, and you will still probably wind up with less in the end for the extra effort. 2) Don't invest 100% of your investment money It always bugged me to let my cash sit idle in an investment account because the niggling  notion of inflation eating up my money and I felt I was wasting opportunity cost by not being fully invested in something. However, not having enough investable cash around to buy into the fire-sale dips in the market made me miss out on opportunities. 3) Diversify The dot.com bubble taught me this in a big, hairy painful way. I had this idea that as a technologist I really understood the tech bubble and fearlessly over-invested in Tech stocks. I just knew that I was on top of things as an "industry insider" and would know when to jump. Yeah. That didn't work out so well. I lost more than 6 figures, at least on paper. Diversification will attenuate the ups and downs somewhat and make the market a lot less scary in the long run. 4) Mind your expenses It took me years of paying huge full-service broker fees to realize that those clowns don't seem to do any better than anyone else at picking stocks. Even when they do, the transaction costs are a lead weight on your returns. The same holds true for mutual funds/ETFs. Shop for low expense ratios aggressively. It is really hard for a fund manager to consistently beat the indexes especially when you burden the returns with expense ratios that skim an extra 1% or so off the top. The expense ratio/broker fees are among the very few things that you can predict reliably when it comes to investments, take advantage of this knowledge. 5) Have an exit strategy for every investment People are emotional creatures. It is hard to be logical when you have skin in the game and most people aren't disciplined enough to just admit when they have a loser and bail out while they are in the red or conversely admit when they have a winner and take profits before the party is over. It helps to counteract this instinct to have an exit strategy for each investment you buy. That is, you will get out if it drops by x% or grows by y%. In fact, it is probably a good idea to just enter those sell limit orders right after you buy the investment so you don't have to convince yourself to press the eject button in the heat of a big move in the price of that investment. Don't try to predict tops or bottoms. They are extremely hard to guess and things often turn so fast that you can't act on them in time anyway. Get out of an investment when it has met your goal or is going to far in the wrong direction. If you find yourself saying "It has to come back eventually", slap yourself.  When you are trying to decide whether to stay in the investment or bail, the most important question is "If I had the current cash value of the stock instead of shares, would I buy it today?" because essentially that is what you are doing when you stick with an investment. 6) Don't invest in fads When you are investing you become acutely sensitive to everyone's opinions on what investment is hot and what is not. If everyone is talking about a particular investment, avoid it. The more enthusiastic people are about it (even experts) the MORE you should avoid it. When everyone starts forming investment clubs at work and the stock market seems to be the preferred topic of conversation at every party you go to. Get out!  I'm a big fan of contrarian investing. Take profits when it feels like all the momentum is going into the market, and buy in when everyone seems to be running for the doors.