Comment by Sir_Cmpwn

From my experience, try having enough projects in your belt that at least one of them has something actionable to do, and work on that while you ruminate on the other problem for a few days/weeks/months. Don't worry about getting anything done soon, prefer getting them done correctly and pick something else up when you get stuck. Also, don't forget that "staring into space for an hour while you think about a problem" is also a valid form of working.