All sound advice. If you have a special reason for wanting to sing a particular song, you might want to tell your audience (but keep it brief!)
And at the end, don't forget the thanks: although some of it may be reiterated by the MC, at least thank the sound engineer, whoever in rhe club gave you the gig, any floor spots/support act. And keep a good song for your encore!
All the best, and let us know how it goes!