When building a puzzle, you don’t start in one corner and work steadily in one direction.
Rather, you start with the easy parts, all over the puzzle.
You build small “islands” of completed puzzle.
Then you start filling in the gaps.
If you think too much about how seemingly impossible the puzzle is, you give up.
So you just take it one step at a time. One island at a time.
Then one day, voila, you’ve finished your puzzle.
Same for building a business.