Bonaparte is showing how to doze off (3)
I believe the answer is:
nap
'to doze off' is the definition.
'bonaparte is showing' is the wordplay.
'is showing' indicates the answer is hidden within the clue.
'NAP' can be found hidden inside 'bonaparte'.
'how' is the link.
(Other definitions for nap that I've seen before include "Racing tip that claims to be a certainty" , "Short sleep on soft surface texture?" , "Short raised fibres on cloth on snooker table" , "Take forty winks" , "A daytime doze" .)