In order to succeed at trading, you must have an edge. Your edge begins with the knowledge you gain through your research and testing that a particular market behavior offers a level of predictability that provides a consistently profitable outcome over time. To get it, you have to know exactly what you're looking for and what to do with it once you've found it.
Without a plan, you'll have no way of monitoring your performance beyond those swings between self-pity and self-congratulation. Without a plan, you'll never break out of the couldawouldashoulda trading session review, if you do such reviews at all (most just try to block the session out, or exercise their selective memory skills in the event that the session just happened to go well and persuade themselves that they are doing so much better than they really are).
Without a thoroughly-tested and consistently-profitable plan and the discipline to follow it, you will never be able to trade emotionlessly (and without such a plan, there's nothing to be disciplined about). Granted that with such a plan you will have to abandon that adrenaline rush that you may have been living for, but at some point this side of bankruptcy one must decide whether he values the rush more than making money. You'd be surprised how many people choose the former.
With a thoroughly-tested and consistently-profitable plan, if you follow it, trading will be much simpler, particularly as your plan will prevent you from taking trades you shouldn't be taking. Unless of course you ignore it. All the trading decisions will have been made ahead of time, so there are no chinks through which fear nor resentment nor anger nor any of the rest of it can insinuate themselves. All you'll have to do is trade.
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