Basically, every time I'm in an instance I run over to a group of mobs and I spam flash about once or twice, then I use my combo Fast Blade > Savage Blade > Rage of Herone. Sometimes I spam flash between each move, and I use Shield Swipe as often as it becomes available.
This is the perfect way to tank if you have a sleeper in your party that is actively sleeping the mob at the start. BLM are great for this, and later level, they can hit all the mob at once with only one AoE sleep.
If only the cnj can sleep mob, try using a defense boost ability right off the bat, at the start of the fight to give your cnj the time to use repose on the mobs before having to cure you. Using cure on yourself is also great for this phase. it help buy the cnj the time needed
If for some reason, there is no sleep available (cnj or blm don't want to, or DD does to much AoE damage that wake mob), The healer will generate a lot of hate curing you since more mob are hitting you. The best way to this is flashing a lot and completing combo on the different mob, as flashing won't be enough later level. For example:
1) Shield lob the first mob.
2) either Fast Blade first mob or Flash depending if all the mob are around you or still coming.
3) defensive ability if there is 2 mob or more left
4) Fast blade or Flash (the one that you didn't use at step 2)
5) Savage blade first mob
6) Flash again
7) Rage of Halone first mob
8) Fast Blade first mob
9) Savage blade first mob
10) Rage of Halone a different mob alternatively (second mob the first time, third mob the second time, etc)
repeat number 8-11 till first mob dies, then repeat from 2
Shield swipe is a great way to do damage (and thus hate) on your main target, it also only cost 40 TP so it's priceless again long fight on boss and should be spamed as often as possible on boss. BUT it take some time since it is affected by the global cooldown, so be wary to use it too much at the start of the group fight, where there is a lot of mob around, you don't want to delay your flash and RoH on a different mob too much.
Small macro tips:
I have a second macro that the classic one for RoH step on 10 (There is 2 RoH slot on my hotbar) it's /ab "Rage of Halone" <mo>, which will do RoH on the mob my move currently is hovering over. That way, I don't have to de-focus the primary mob that the team is currently killing. I do the same thing with my provoke macro.
Hope this help.