In pro mode, you want to first see the subject. ISO needs to be up to lighten the subject, than shutter speed needs to be just so, so that it allows just enough light to see the subject, darker the area, the slower the shutter speed, but keep a steady hand (a tripod or stand will help). Than the focus... the subject should be crisp, not blurry. White balance is to your tast. .. do you want a warmer or cooler picture?
The exact setting though I cannot give you because I don't know your subject or photography conditions... all I can say is play around with it. Have fun with it... I have faith your pictures will come out just fine.