Relax away from home beneath cloudy slope (5,3)
I believe the answer is:
chill out
'relax' is the definition.
(I've seen this before)
'away from home beneath cloudy slope' is the wordplay.
'away from home' becomes 'out' (synonyms).
'beneath' means one lot of letters go next to another (in a down clue).
'cloudy' becomes 'C' (meteorological abbreviation).
'slope' becomes 'hill' (sloped area of land).
'c'+'hill'='chill'
'out' put after 'chill' is 'CHILL OUT'.
(Other definitions for chill out that I've seen before include "Relax (informal)" , "Relax after energetic spell" , "Calm down, relax" , "rest" , "Relax (inf.)" .)