Don't taunt first.
Many tanks open with a taunt. Taunt builds a % of threat above the highest threat on the list. Taunting at the start is a waste. Go through a full ration and then taunt (or before hand if target switches)
Turn target of target on and keep it in a place that you can easily see. Make sure you are always aware of who your target is focused on.
So very much this... and seriously, don't pull with your taunt, ever