Here are my examples as a L39 sorc.
. While kiting, I'd use this priority list:
1. Death Field
2. If Wrath is active, Crushing Darkness
5. Force Lightning to proc Wrath
. I'd use this priority list:
1. Bubble yourself. Yes, yes, it's the most hated ability at the moment, but you have it, so use it.
4. Crushing Darkness
5. Polarity Shift
6. Force Lightning with Lightning Barrage
7. Chain Lightning with Lightning Storm
8. Lightning Strike or Force Lightning
The most important part is, as said before, to stay alive. Keep a low profile, don't stand in the middle of the zerg and kite melees to the best you can. If you're target by snipers or mercs, try to LOS them while getting your dots up.
EDIT: Regarding gear, they also matter sub 50 but not to the same degree as in 50 PvP. keep your armor up to date in blues through commendations and also don't forget to upgrade your earpieces, implants and relics. the latter aren't used in PvP but they give extra endurance.