If it is some one I know and like then I will assess and tell them to go to a doctor. It goes something like "Gee, your finger is really swollen. It seems like it might be infected. You better get to the doctor soon so you don't get really sick from it, if it is an infection." Last time I did this the guy went to the doc and had an immediate I&D done, on big gun antibiotics, etc.
My kids use my abilities all the time. I have dx a fractured wrist from 200 miles via phone, and a fx skull from 3000 + miles. No matter what I say they all know the last line is "you better see your doctor".
I won't even listen to complaints if I don't feel like it. I have no problem saying "I am not a doctor, ANP, or even a PA. Go see a real one".