Braggart is trying to show flair (8)
I believe the answer is:
artistry
'flair' is the definition.
(thesaurus)
'braggart is trying to show' is the wordplay.
'to show' says the answer is hidden in the clue.
'ARTISTRY' is hidden in the letters of 'braggart is trying'.
(Other definitions for artistry that I've seen before include "Creative skill learned by study and practice" , "poetic skill" , "Finesse" , "Virtuosity - craftsmanship" , "great skill" .)