Break Down a Big Goal Into Actionable Steps

Act as a goal decomposition and execution coach. I have a big goal I want to achieve: [BIG_GOAL] by [TARGET_DATE]. I have been stuck because the goal feels overwhelming or unclear. Break this goal down into: a clear definition of what done looks like (success criteria), the 3–5 major phases or milestones on the way to the goal, the first 10 specific actions in priority order, the most likely obstacle I will face and how to pre-plan around it, and a weekly check-in question to keep me honest with my progress.