1. Don't be afraid of paying taxes. So many people don't exercise their options because they fear the taxes that will hit them that year. Don't be so afraid. If your stocks are at a great price, and you want to sell, take advantage of that opportunity.
2. Don't beat yourself up for a loss. Again, in the same vein deciding when to sell is extremely difficult. Nobody wants to have to take a loss, but you want to profit off of your investments. That means eventually you just have to take the jump and hope for the best.
3. Buy damaged stocks, but never a damaged company. You always need to look to the long term earning potential of a company before you make the decision to invest. If they don't have a good long term outlook, then it's not someone you want to invest with. That's a fact.
4. Diversify your investments. That can mean investing in several different companies to limit the possibility you could be hit with a big failure. But that also means diversifying the type of investments that you make. Don't just play stocks, look to commodities, and also look to investing in things like bonds. There's a lot of money to be had in diversifying your portfolio.
5. Don't invest in a company that can't keep a hold of a CEO. There's a reason that CEOs run for the hills repeatedly from one company. If you're not hearing the full story, but they've got a never ending revolving door at the top, it's not worth your investment because there's always something else going on.
These are tips that can really get you started, and ensure that you at least have a chance at success in the markets. Just be prepared to take some risks, but play smart too, and understand when a risk is just not worth the taking just like Igor Cornelesen will tell you.