My approach to satisfactory results
It's a three step process
Usually you find yourself in one of the three stages without having the other two worked out. And usually you do not get satisfactory results.
It is also important to apply this process to every step of the big project—not to the big project itself. This helps to not get stuck.
Each of the three steps is equally important and, in a way, equally "hard".
It is ok to start at any step, just make sure you provide the fundament by working on the other two.
It is still an open question if deciding that something is important is a voluntary action or something that needs to be tuned against your inner camertone.