The dollar is practically worthless so I am not going to mention figures. Enough to say that in ten years I "
feltornasztam magam" (a graphic Hungarian expression of a person making gymnastic exercises in a tree - finding himself suddenly in the upper branches). In my learning process, my most vivid memories are of course those of the failures. Examples:

(1)
I started investing in local liquid bonds through my bank. The bank used to give buy orders without limit and after a time I discovered that I was always paying more than the current price. I suspect it was because of the banker's sheer contempt towards an ignorant client. The man is still there, fatter and promoted to dept. manager.
(2) I started buying mutual funds. Soon I understood that those investing in shares produced better results. It took me several years to learn that I was paying 4 - 5% per year for something I could do better than the fund manager, like building a portfolio. It took me time to understand that I was buying the Bank's funds for the illusion of paying less fees. Today banks cannot have funds nor give advice.
(3) Having succeeded in selecting good shares, I got interested in small cap stock. Bought many books, read all the MAYA publications (TASE's webside), wrote in all the boards and started speculating in small cap and options. In balance, I think I made money, but I found difficult to sell papers that had no regular markets. In the end, I was stuck with some unsaleable options which lost all their worth.
(4) I was fascinated by oil price fluctuations and its potential for profit. I studied the market and discovered seasonal fluctuations which seemed - statistically - reliable. I bet that oil was going to be under 60 dollars a barrel, but then Americans started to invest in oil futures to station their money (today it is illegal) and they drove up the price over 100 dollar. I lost.
The right thing I did was to avoid panic during the crisis and accumulate stock at low prices. Another good thing was to avoid following expert advice, which pushed people to invest in foreign markets (briefly I bought Chinese funds, and happily sold it at profit).
But the most important lesson I learned in this ten years is to invest in things I know personally and understand, like Israeli companies that I had worked for and admire. For example, a few years ago I had to do a work for Periclass in Nahal Zinn, an infernal chemical dust site in the most god-forsaken desert. I met a Hungarian Jew sitting in a derelict air conditioned hut who explained me what they were doing. It was very clear. I started to collect the shares. They are worth now ten times more. Lately I have been working with food factories, but I cant see them making money. I was among the first to identify the coming scarcity of sand and other building materials in Israel, and studied the recycling business, but I didnt follow up. Now there are several thriving building materials recycling plants, it did not require much investment, but I lacked the drive. Now I see that new building materials and accesories are displacing old materials (like new glasses, new aluminium and titanium linings, new water saving toilets, and so on) but I have no time.

THE important thing is to read all the time and to read everything, to collect, to write down and to think about what is going on. Gary (see link on blogroll) is the most disciplined practitioner of this method, and I think he is very successful as fund manager.