Don't waste time and impede car's design (5,4)
I believe the answer is:
carpe diem
'don't waste time and' is the definition.
I can't judge whether this defines the answer.
'impede car's design' is the wordplay.
'design' is an anagram indicator.
'impede'+'car'='impedecar'
'impedecar' with letters rearranged gives 'CARPE DIEM'.
Can you help me to learn more?
(Other definitions for carpe diem that I've seen before include "Seize occasion" , "Gather ye rosebuds" , "make the most of today" , "Make the most of the time you have" , "'Seize the day'" .)