So regain in order to coordinate (8)
I believe the answer is:
organise
'coordinate' is the definition.
('organise' can be a synonym of 'coordinate')
'so regain in order' is the wordplay.
'in order' indicates anagramming the letters (the letters in a new order).
'so'+'regain'='soregain'
'soregain' is an anagram of 'ORGANISE'.
'to' is the link.
(Other definitions for organise that I've seen before include "Devise and direct" , "Ignores a move to make ready" , "Arrange in a systematic or orderly way" , "Arrange, plan or direct" , "Arrange - as region (anag)" .)