Take turns hill-climbing before cooking tea (6)
I believe the answer is:
rotate
'take turns' is the definition.
(rotating is a kind of taking turns)
'hill-climbing before cooking tea' is the wordplay.
'hill' becomes 'tor' (tor is a kind of hill).
'climbing' says the letters should be written in reverse (in a down clue, letters climb up).
'before' says to put letters next to each other.
'cooking' is an anagram indicator.
'tor' backwards is 'rot'.
'tea' anagrammed gives 'ate'.
'rot'+'ate'='ROTATE'
(Other definitions for rotate that I've seen before include "Turn round" , "Go around" , "Revolve" , "Go round and round" , "Make to spin around" .)