Drink with Don to build ties, say (8)
I believe the answer is:
neckwear
'ties say' is the definition.
(I know that necktie is a type of neckwear)
'drink with don' is the wordplay.
'drink' becomes 'neck' (to neck a drink is to drink it quickly).
'with' says to put letters next to each other.
'don' becomes 'wear' (synonyms).
'neck'+'wear'='NECKWEAR'
'to build' is the link.
(Other definitions for neckwear that I've seen before include "eg Ties, cravats" , "Collars, ties etc." , "sort of clothing" , "Stock" , "Tie perhaps" .)