Just lightly tap them together for short periods. I think some subdued grunting might be more appropriate. However, things seem to be early this year so I'm not sure. I shot a thick-necked buck last Saturday. Guys I know are have seen scrapes and I've heard of some sparring already. Do a little calling but no so much that you could spook them. Right now they might come in more out of curiousity than aggression.