Hurry up and use the foot-lever (4,2,2)
I believe the answer is:
step on it
'hurry up' is the definition.
(I've seen this before)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for step on it that I've seen before include "Go faster - put foot down" , "Go for speed" , "Be quick" , "So join the escalator" , "Hasten" .)