To develop one's approach or strategy to a project while carrying out that project, and not beforehand.
build a better mousetrap
To create a new product, method, or idea that is better than an existi…
build up
To accumulate: to increase incrementally or continually.
build castles in the air
To have any desire, idea, or plan that is unlikely to be realized; to …
build on sand
To put something in an unstable position by failing to give it a secur…
build bridges
Often followed by between or to: to establish friendly relations or li…
build a case
to compile evidence that supports a charge against someone.