You don't...
When using it, tear off a small (50p-ish) sized bit and chuck it once finished with. You can 'demote' it to use on your wheels, but certainly shouldn't be reusing it again and again.
I've just picked up my Mini and need the time to do a 'proper' clean, polish and wax. Unfortunately its a full days' work and I simply don't have the time at weekends anymore.