Since you're just starting PvP, I'll give you an overpowered, and rather easy, team. It's very discouraging to get hammered for battle after battle when you're just starting.
Magical Crawdad - Surge, Shell Shield, Wish
Bone Serpent - Bone Barrage, Call Darkness, Nocturnal Strike
Mechanical Pandaren Dragonling - Breath, Thunderbolt, Decoy
P.S. I suggest putting the pets in that order in your team, to muddle expectations. People do first think you're going to lead with your first pet. Experienced battlers know better of course, but I think even they are affected or slowed somewhat by first impressions.
What you do depends on your opponent, of course. If he looks like he's starting with Lil' Rag, for example, you would lead with your Crawdad for the strong damage, and shield and heal yourself appropriately.
However, a lot of what you meet will likely be the typical Graves and the Evil Undead (feat. MPD) teams. Against these, you will probably:
1. start with the Serpent
Bone Barrage, Call Darkness, Bone Barrage, Nocturnal Strike
for some big single target damage and to make the skies unsafe for MPDs
2. then swap to the Dragonling with your Serpent at half health. The Dragonling will stall with
Thunderbolt, Decoy, maybe a Breath
3.finally you bring in your Crawdad, and just as Darkness ends do Wish...
4. and then swap back to your Bone Serpent, which receives the Wish heal, puts up the Bone Barrage again, and carries on.
You do have a call to make when swapping out the Serpent in the first place. If it has low health, and the opponent has an AoE team that will kill it on the back line, it may not make sense to swap the Serpent out. If it has taken a crit early, it might even make sense to swap it out before its Nocturnal Strike, if you're sure you can revive it with Wish later.