Here is what I do on Healing Beorning:

1. To begin with, always start the fight with max Wrath. You can use Biting Edge, Hearten and Ferocious Roar to fill up your Wrath pre-fight.
2. Put the Mark of Grimbeorn on your top DPS player in group to give them a buff of +15% damage for 12s, whenever you use Vicious Claws. However, you will lose out on some healing on tank if you do this, so if your Tank needs more heals, switch the mark on the Tank.
3. Always start the fight with your debuffs right away, Bees first (don’t forget to swap to unimbued weapon if you have, for the debuff duration). Also put the Mark of Beorn on the target you want to use Bees on.
4. Ideally you want to use your Armour Crush debuff when Oathbreakers are on target, so you can coordinate that with your Captain, but if your group is not using Oathbreakers at start, use your Armour Crush right away after you use your Bees.
5. Now that both of your debuffs are on the target, go in Man Form and use Slash. Ideally you want to use this skill 3 times every 20 seconds, so whenever you go in Man Form, use Slash. It gives a nice outgoing healing buff. It helps if you can track this buff via a plugin.
6. After these 3 things are done, you want to start using HoT (Hearten) on your tank, or whoever that is taking heavy damage.
7. Rotate around Slash – Hearten – Nature’s Mend – Slash
8. After you have finished your Man Form rotation, your debuffs will be coming off, go in Bear Form and Refresh them.
9. Stay in Bear Form and look around who needs heals. At this stage you can also start building Encouraging Roar stacks on your tank, just to be safe, it’s a very strong HoT.
10. If group needs an AoE heal, use Rejuvenating Bellow, your 2nd biggest AoE heal.
11. You also have Relentless Maul, your biggest AoE heal, use this only if your entire group needs some form of a heal.
12. After your group’s morale is stable, switch back to Man Form and start the rotation again, Slash – Hearten – Nature’s Mend – Slash
13. You also have some other emergency skills, such as Nature’s Bond, which transfers almost all the healing you receive, to the person you use the skill on, it’s very effective, use it on the person (usually the Tank) to bring them back up fully.
14. Another important utility is the skill called Sacrifice. If you have used up all your heals and cooldowns and have nothing left, use Sacrifice on the target. But be careful with this, if you receive too much damage on yourself after using that, turn it off fast).
15. There’s also another important skill to keep track of, called Piercing Roar, it reduces target’s damage by 20% for 12s. Ideally, this skill should be used before a big incoming hit. If you know the mechanics well, you can use this skill well and take advantage of it. However, if you don’t know the mechanics, keep this skill on cooldown.
16. To summarize, you need to keep Armour Crush and Bees (with Mark of Beorn) full time 100% on the DPS target. After that, it’s all about using Man and Bear Form heals and HoTs, when they are on cooldown, switch to other form and use heals from there. Keep Slash buff up, it’s very potent, and Hearten HoTs and Encouraging Roar HoTs on your Tank as best as you can. Use Biting Edge/Slam/Ferocious Roar/Nature’s Mend also in rotation, so your Wrath doesn’t disappear.