How hard is it to transfer into Northwestern University?

<p>My grades throughout high school weren’t great so I didn’t apply. I knew I had didn’t have a chance at being accepted. Northwestern is really my dream school though. I plan on going to another college and then transferring. What should I do to guarantee I get accepted? How many semesters should I complete in another school before I try to transfer? & will my high school history still be relevant?</p>