ok i will answer your questions, based on what you have posted
ISO Speed - we do not know your camera, so you will have to answer this yourself.
Since you do not want to bring along a tripod, you will possibly need as high an ISO speed as your camera can do with acceptable results, test it and decide
fstop/aperture - it depends on the amount of DOF that you need for that particular shot
Shutter Speed - depends on the ISO and fstop that you have selected to give an acceptable exposure for the lighting situation there. but adjust to make sure you don't get camera shake, of course if you had brought along your tripod, that will not be an issue.
what to look out for - distracting elements in your frame, read up on composition
what not to do - basically do not make a nuisance of yourself and enjoy yourself
after the shoot, go back and review your shots and figure out what went right/wrong, why it went right/wrong. And what could you have changed to make the shot better.