(and for many other things in life)
Analyze the mission. Understand higher headquarters’ mission, Commander’s Intent, and endstate (the goal). Identify and state your own Commander’s Intent and endstate for the specific mission.
Identify personnel, assets, resources, and time available.
Decentralize the planning process. Empower key leaders within the team to analyze possible courses of action.
Determine a specific course of action. Lean toward selecting the simplest course of action.
Empower key leaders to develop the plan for the selected course of action.
Plan for likely contingencies through each phase of the operation.
Mitigate risks that can be controlled as much as possible.
Delegate portions of the plan and brief to key junior leaders. Stand back and be the tactical genius.
Continually check and question the plan against emerging information to ensure it still fits the situation.
Brief the plan to all participants and supporting assets. Emphasize Commander’s Intent. Ask questions and engage in discussion and interaction with the team to ensure they understand.
Conduct post-operational debrief after execution. Analyze lessons learned and implement them in future planning.
(via and my own experience in combat)