Improvised lying perhaps holding German newspaper back (2,6)
I believe the answer is:
ad-libbed
'improvised' is the definition.
('ad-lib' can be a synonym of 'improvise')
'lying perhaps holding german newspaper back' is the wordplay.
'lying perhaps' becomes 'abed'.
'holding' indicates putting letters inside.
'german newspaper' becomes 'bild' (German daily newspaper).
'back' says the letters should be written backwards.
'bild' written backwards gives 'dlib'.
'abed' going around 'dlib' is 'AD-LIBBED'.
(Other definitions for ad-libbed that I've seen before include "Performed without preparation" , "Spoke off the cuff or impromptu" , "Spoke impromptu, improvised" , "Extemporised" .)