Rubbish I used to kick? (2,4)
I believe the answer is:
my foot
This clue is a double definition.
'rubbish' is the first definition.
(phrase used to dismiss something as rubbish)
'i used to kick?' is the second definition.
(you kick with your foot)
(Other definitions for my foot that I've seen before include "bunk!" , "I just don't believe it!" , "Interjection expressing contemptuous disbelief" , "I've some nails here?" , "Definitely not" .)