Adapt. That's the name of the game
What worked once will not necessarily work twice. Use proactive failure analysis. Essentially, you have to methodically discard the plans, possible solutions and schemas that would likely fail based on the analysis of the problem at hand.
After collecting as much intelligence as you can, after you have performed recon and observed your target, either physical or digital, you then can red team your own solutions. You use proactive failure analysis to discard the solutions that might fail based on the intelligence you just collected. You then adapt the remaining solutions to this same intelligence and prepare the main, contingency and emergency plans.
This same technique is used by attackers. They adapt based on their failed attacks, they analyze what happened and factor this into their future attack plans.
(Originally posted on Small Team Tactics)