Alight, boogie! (3,4)
I believe the answer is:
get down
I believe this is a double definition.
'alight' is the first definition.
(I've seen this before)
'boogie' is the second definition.
(both can mean to dance)
(Other definitions for get down that I've seen before include "Swallow" , "Dismount, alight" , "you could - from duck" , "See feathers, > alight" .)