I never cut my scraps till I decide on a project. I know many cut into specific sizes , but just when they are all cut , a pattern with a size different from the pre- cut scraps will present itself.
Do develop a system , by color, or type it will help when the right project presents itself.
There are those who just aren't scrappy quilt makers ,if that is you.... free yourself of this burden, and donate them or offer them here in the donation section.