The hardest part is getting the stone rolling in the first place. You make sure you’ve got a big enough stone and a tall enough hill. You spend the time rolling it all the way to the top and then aim it at your target. There is the period of planning and the period of execution. For me as a writer it is more like a period of creativity and a period of editing. The key is that you do the first part so that the second part is set up to gain momentum, this is where you get your exponential gains and true breakthroughs.
Once you’ve put it into motion then you just have to keep up and do small maintenance things to make sure it stays in motion. Most people can’t even get to this point because they can’t decide what direction they want to roll or can’t find a big enough stone or a tall enough hill. The tough part is when you want to change directions after you’ve built up some momentum. So that you have to stop the whole system and spend some time away from the world to rebuild everything. Until you’ve set it into motion once more and breathe a sigh of relief when the momentum picks back up again.