Only real thing I can say is always attack from the air. You just do the one swing then the shield body slam, which is really what gets you 90% of your kills and dps. In both pve and pvp. It has way better tracking, hit detection and damage. Attacking on the ground uses two light attacks first, which wastes super energy on attacks that probably won't hit much in the first place. I've been maining sentinel since D2 launch. It annoys my friends hah.