What a retarded title. There are no main rules of investing, you do what you feel and what you want not what people suggest especially ones that have little to no clue.
Have to agree with you there. In the past, I have followed advice from various market researchers and economists. I always ended up in a loss. After that I stopped following their advice, did my own research and took my own decisions. I am able to get an annualized ROI of almost 20% for the past 4-5 years. So here is my advice. Take your own decision, and listen to none.