Trading plan
A trading plan is the written document that defines your markets, hours, entry and exit criteria and risk rules.
A plan answers in advance the questions you would ask yourself under pressure: which markets, which timeframes, what conditions to enter, where to place the stop, how to exit, how much to risk, when to stop for the day.
It turns trading into a repeatable process. Without a plan, every decision is made in the emotion of the moment, and you can never tell whether a loss came from the method or from an execution error.
A good plan fits on one or two pages. Reread it before each session, and only change it calmly, at the end of the week, based on the numbers in your journal.