A tip from my vocal coaching of singers:
ALWAYS, be honest. Never “perform.” Your audience can smell a phony a mile away and will not respond to a “performance.” (in the sense of “performing” a song with no emotional understanding or connection) Reach them with honest emotion. Imagine each audience-member as a one-to-one conversation. Do not be afraid to infuse your performance (in the good sense of that word) with real, heartfelt feelings and your audience will join you and become partners with you in real, honest communication.