I learned this rotation from a veteran warg, and it has worked really well for me. So I use shadow pack (if possible), pounce, claws, rend flesh, eye rake (to speed rend), claws, maul, cripple. After this, I land the silence if needed, then start spamming claws, rend, and maul. I like to save pounce to interrupt inductions, and eye rake to speed long animation skills (e.g, flea bitten, savage fangs).
On a side note, I actually try to stun burgs at the beginning of a fight whenever possible in order to get them to burn FF. If they use it at the beginning, the heal goes to waste and the evade boost counts for nada if you are in Shadow. Later in the fight you can stun them with impunity, and such stuns have actually allowed me to win a few 1v1s. However, it'd be best not to stun them if you are in a group composed of non-wargs, as the evade boost greatly complicates things for your fellows. 'Tis all about prudence.
Anyway, I hope this info is of some use to you, and gratz on your warg!
"The strength of the pack is the wolf; the strength of the wolf is the pack"
-Motto, U.S 3rd Light Armored Recon Battalion
Leftenant Arkantor: Oblivion Awaits