Strut your stuff
Definition 1 of 1
Pro Tip 1/3Cultural Vibrancy
Often used to describe lively and confident behavior in a performance or social context. 
She loves to strut her stuff in the annual talent show.
Pro Tip 2/3Not Arrogant
While it implies confidence, it's not the same as being cocky or arrogant. 
At the fashion show, he'll strut his stuff, but he always remains humble.
Pro Tip 3/3Positive Encouragement
Can be used as encouragement to promote self-confidence in others. 
You've practiced hard, now go strut your stuff on the field!