Nice thread.
Here is what I think were my major mistakes, other than the tens of mistakes that I made in the beginner stage.
Looks like some of the points (mistakes) are very specific to me. What works for me might be mistakes for others, and vice versa. There is a book (I don't remember the name - I think it is by Brent Penfold, though not sure), in which the author contrasts the trading methods of different successful traders. For example, one says that SL are for fools, and another swears by SL. Buffet is for Buy-and-hold, and someone else doesn't agree.
1. Discretionary Trading: Discretionary Trading doesn't seem to work for me, though it works for many other traders. Nowadays, I only paper trade my discretionary thoughts, with the objective of deriving mechanical rules from the paper trading insights. Thinking during runtime is a big no-no for me. My last set of discretionary (paper) trades are posted in
http://www.traderji.com/members-discussion-forums/98974-still-not-doing-right-8.html#post1225746.
2. Not backtesting before going live: I have done this mistake hundreds of times, and recorded many of the trades in my trading diaries in Traderji, only to realize that the method was a loser after spending money and time. Backtesting could have saved me a lot.
3. Incorrect money management: Many times, I have made good money, only to lose it due to bad MM. For example, In Jan 2016, I made over 200% with an un-backtested discretionary entry system, but gave back all the gains in the next 3 months, trading the exact same method
http://www.traderji.com/members-discussion-forums/98974-still-not-doing-right-4.html#post1130381. I later realized that this strategy would have worked with a lower risk per trade, but with less impressive returns. However, depending on the win % and RR ratio, the optimal risk % may be different for different systems. In my current trading method that I have been trading for over 8 months now, I risk 15% or more of my capital in every trade, and am still surviving with good returns.