Formal:
* Plan: A detailed proposal for achieving something.
* Tactics: Specific actions or methods used to achieve a goal.
* Scheme: A plan or program of action, often secret.
* Approach: A way of dealing with a situation or problem.
* Framework: A basic structure for a plan or approach.
* Roadmap: A plan that outlines the steps to be taken to achieve a goal.
* Blueprint: A detailed plan or design.
Informal:
* Game plan: A plan for achieving something, especially in a competitive situation.
* Course of action: The way in which someone plans to deal with a situation.
* Method: A way of doing something.
* Approach: A way of dealing with a situation or problem.
* Line of attack: A particular way of approaching a problem or situation.
More specific:
* Campaign: A series of actions designed to achieve a particular goal, especially in marketing or politics.
* Policy: A plan or course of action adopted by a government, business, or other organization.
* Methodology: A system of methods used in a particular field of study or activity.
The best choice will depend on the specific context and the desired tone.