My opponent has made the opening lead out of turn--Now what?
First of all, so it won't happen to you, remember to always make your opening lead face down. Give everyone at the table a chance to tell you if it isn't your lead. You can take back the face-down lead without any penalty.
But, if an opening lead is made face up (out of turn), the first thing to do is for the declarer to (politely) call for the director. Don't make your own table ruling.
There should be no ac