The simplest version is plan adherence. After each trade, mark whether you followed the plan: the setup was in your list, the stop was set before entry, the size was as planned. The score is the number marked yes divided by the number marked. Followed on 38 of 50 trades is 76%.
The score only means something if the rules are specific enough to be judged yes or no. Be patient is not checkable; no entry within ten minutes of a loss is. It also depends on honest marking, so mark immediately and mark the rule, not the result.
The most useful comparison is not the score itself but the expectancy in R of followed and not-followed trades. If breaking the plan costs more per trade than following it, the score has a price you can quote. If it does not, the plan may be the problem.
Beware of treating it as a target to maximise at the expense of judgement. A rule that never fits reality should be revised on a schedule, not ignored trade by trade.
Reflect weights this plan-adherence figure most heavily when it builds its overall profile.