Manage somehow to form party (4,2)
I believe the answer is:
'manage somehow' is the definition.
(to make do is to manage or cope)
'form party' is the wordplay.
'form' becomes 'make' (synonyms).
'party' becomes 'do' (do is a kind of party).
'to' is the link.
(Other definitions for make do that I've seen before include "Using what little is available, manage" , "Cope" , "Improvise" , "Makeshift, temporary" , "Manage with something not fully satisfactory" .)