Being disciplined is a crucial character trait if you want to become a better trader.  If you lack discipline, you will not be a good trader.  That's the bad news.  The good news is that most people can become disciplined when it comes to their trading.  As a bonus, if you start becoming disciplined in your trading, you will see that the discipline will start spilling over into your life outside of trading. 

To become more disciplined, all you have to do is start taking small steps towards being disciplined.  An example of a small first step in being disciplined in your trading is to place a stop on every trade as soon as you place your trade.  Once you have done this on every trade for a month then think of the next thing you can apply discipline to.  Such as only move your stop in the direction of the trade and never remove your stop.  Keep going like this and you will become a disciplined trader.

So who is a disciplined trader?  It is a trader who logs in all their trades into a trading journal and then reviews their trading journal every week.  It is a trader who sticks to their buy and sell points.  It is a trader who places a stop after every trade is entered.  It is a trader who always follows his stops, never removes or lowers his stops and only moves the stop in the direction of profits.  It is a trader who treats trading like a business and sticks to his business plan, trading plan and money management strategy.  Finally, it is a trader who PROTECTS HIS CAPITAL.