While i'm not the best at it, this is the advice that has been given to me. Keep an eye for any spawning adds. When they appear, move over as fast as possible and whack em with whatever ranged attack you have as your tank. At that point, do a combo on them just to build up hate and then switch back to whatever mob the dps is focusing. If it's multiple adds at the same time(like the dogs in Sastasha's mini-boss), hit as many of them as you can at once with your aoe and go for the rest as soon as possible. If need be use multiple aoes before attempting to build hate on them via single target combos.
Like I said, I'm not an expert but this was advice given to me by other tanks that has worked well, at least for me. Good luck!