This is a short video that goes over the rules of freestyle and greco-roman wrestling, tactics (controlling the centre, out the ring etc) and I thought would be an informative resource. He describes his own tactics (the last move, imposing will etc). It's presented by olympian Jake Herbert. https://www.youtube.com/watch?annotation_id=annotation_1603642039&feature=iv&list=PL-292yfpAFGZeXXpJ3V8ZeqW4g_887hJ9&src_vid=cjBTY5YajAg&v=N_58GH8HpOI