Creating and maintaining a trading journal is one of the most important things to do in professional trading.
You need a trading journal because you need to track your trading performance over time. Many traders get caught up on the results of each individual trade; however, as a professional trader, you need to know that your trading performance is measured over a long series of trades, not just one or two. So, it’s important to have a way to track your results so that you can see how you are doing over a series of trades, this allows you to not get caught up on any individual trade. You can think of your trading journal as a constant and reminder that your trading performance is measured over a series of trades. Having this type of recording is very important, it helps keep you focused and remove any emotion you might attach to any one trade.
Creating and maintaining a trading journal gives you the structure required to build your trading routine on and it also helps you examine and focus on each individual element of a trade.
You can have more than the above suggested that you think will help you.
Documenting your trading results is a necessary component to becoming a professional trader. As your trading journal progresses over a series of trades, you will start to see the significance of it more clearly. The power of risk reward and money management will become glaringly evident to you as you look over your trading journal after a few months go by. Having this piece of evidence to explicitly show you how discipline and patience pay off over time, is a critical element to attaining and maintaining the proper trading mindset. Creating and meticulously maintaining a trading journal is the quickest and most effective way to develop into a disciplined and profitable trader.
Hope you start yours immediately :)