Manner, technique (6)
I believe the answer is:
method
This clue is a double definition.
'manner' is the first definition.
(method is a kind of manner)
'technique' is the second definition.
(I've seen this before)
(Other definitions for method that I've seen before include "Tidy way of doing things" , "System (of acting?)" , "Way of doing something, even in madness (6)" , "Kind of technique, may be present in madness" , "Order" .)