Eight yes-or-no questions to answer before every entry, and why the habit has to be built before money is on the line.
Does the setup match the plan, yes or no, not "kind of"? Is the stop placed where the idea is wrong? Did the position size come from risk divided by stop distance? Is the liquidation price at least three times the stop distance away? Is funding checked? Is there no scheduled event in the next sixty minutes? Is this at most my third trade today? Am I outside the twenty-four-hour lockout after two consecutive losses?
Eight boxes. If one is empty, no trade. It feels silly for about a week. Then it quietly prevents the trade that would have emptied the account, and you will not even notice, which is the point.
Run the checklist on paper trades too. A habit has to be automatic before money is at stake, and rehearsal is only free in a simulator. Once the list takes twenty seconds without thinking, you are ready to use it where it matters.