I fold my stash in three different sizes;
large amounts are folded as they are at the LQS (although without the cardboard center-takes up room that I can use for more fabric)
medium amounts of fabric are folded to look like books (standing up on their sides, about 1/2 the height of bolted fabric-you'd be amazed how much fabric you can fit in a cabinet that way-again no cardboard centers-allows more room for fabric)
1 yard or less pieces-folded the size of fat quarters and stacked vertically.
All medium and small amounts are in color groupings. All large and medium fabrics are in my cabinet that has doors. My small sized fabrics have been bumped to one of our book shelves, as there's no longer space in the cabinet for them. But I'm always on the lookout for a larger cabinet that can hold all of my cotton fabric. All flannel is in a different shelving unit in a closet upstairs.