"Writing down the problem" sounds trivial, but it's often the hard part. Once you understand the question, the answer is obvious (as a commenter said).

I have to break down complex problems in order to come up with questions that I can understand. The really hard part is in finding the right way to break them down, because not all modularities and boundaries between them will help to solve the problem. But all of this properly forms part of Feynman's step one, of writing down the problem.

I also often get a sense of what the answer should be - but it's very difficult to even begin to describe it in words, let alone define it clearly, and even harder to prove it is correct. Yet... it almost always is correct. This is properly in Feynman's steps two and three.

Computers are useless. They can only give you answers - Picasso

It is by logic that we prove, but by intuition we discover - Poincaré

and so another, even bigger, computer had to be built to find out what the actual question was - Douglas Adams