You will need a larger-sized appliance with a shredding disc attachment - a flat, round attachment with holes similar to those on a box grater. Follow your manual for getting it all set up, then press your cabbage through the shoot. Obviously, you can’t shove a whole head of cabbage through a food processor. Instead, slice it in half through the stem and again to make quartered wedges. If you only have a smaller appliance, it will be fast to simply shred the cabbage by hand instead of working in batches.