strut one's stuff, to dress, behave, perform, etc., one's best in order to impress others; show off.
Origin: before 1000; Middle English strouten to protrude stiffly, swell, bluster, Old English strūtian to struggle, derivative of *strūt (whence Middle English strut strife)
Related forms
strut·ter, noun
Synonyms 1. parade, flourish. Strut and swagger refer especially to carriage in walking. Strut implies swelling pride or pompousness; to strut is to walk with a stiff, pompous, seemingly affected or self-conscious gait: A turkey struts about the barnyard. Swagger implies a domineering, sometimes jaunty, superiority or challenge, and a self-important manner: to swagger down the street.
"supporting brace," 1587, perhaps from strut (v.), or a cognate word in O.N. or Low Ger. (cf. Low Ger. strutt "rigid"); ultimately from P.Gmc. *strutoz-, from root *strut- (see strut (v.)).