Getting Unstuck
Most of the times I've been stuck on something, the problem wasn't the thing itself. It was that I'd stopped believing I could make progress on it, and every hour I spent on it after that point was really just an hour spent confirming that belief.
The fix is almost embarrassingly simple: do the smallest possible version of the task. Not the smallest reasonable version — the smallest version that still counts as starting. Open the file. Write one bad sentence. Sketch the ugliest possible diagram of the system. The point isn't the output, it's proving to yourself that the thing is touchable.
Once something is touchable, momentum takes over on its own. You don't need discipline to keep going once you're already going. You need it only for the first move, and the first move can be made arbitrarily small.