I've bought several 12 x 12 pads of printed cardstock over time andhave been storing them separately from the card-sized stuff. So today I decided that, since I really use it all for cards, I would cut it down to suit that.
Depending on the pattern I cut some to 6 x 6, some to 5.25 x 4, and some I cut to feature items on the cardstock. The 'backgrounds' stuff in 6 x 6 all went into the box with the stuff from 6 x 6 pads
The feature items got set aside in another box so they are ready to pull out for card fronts
Then all the smaller bits got sorted in with the table scraps for use as 'whatever'
Now I'm all stocked and ready to make a bunch more cards.