Trained in due fashion, having acted badly (8)
I believe the answer is:
educated
'trained' is the definition.
('educate' can be a synonym of 'train')
'due fashion having acted badly' is the wordplay.
'fashion' is an anagram indicator.
'having' is a charade indicator (letters next to each other).
'badly' indicates anagramming the letters (letters in the wrong order).
'due' is an anagram of 'edu'.
'acted' with letters rearranged gives 'cated'.
'edu'+'cated'='EDUCATED'
'in' acts as a link.
(Other definitions for educated that I've seen before include "Learned - cultivated" , "Civilised" , "Cultivated, knowledgeable" , "Enlightened, knowledgeable" , "Having completed schooling, well informed" .)