set out to do
set out to (do something)
To begin to do something with a specific intention in mind. We've set out to create the most elegant and user-friendly smartphone ever made, and by God I think we did it.
set out to do something
to begin to do something; to intend to do something. Jill set out to weed the garden, but pulled up a few valuable plants in the process. I set out to repair the door, not rebuild the whole porch.