Along with what Ailitardif said, Healbot is nice. It does take some getting used to, but does help a lot. My first few times running Kara, I didn't use heal bot (just had the raid on my screen and pushed buttons). The raid was surprised that I was healing that way, but once I got healbot, I was even better than before.
It is a bit "lazy," in the sense that all you have to do is click on people's name to heal them, but when you're spamming heals, it's a lot easier.
And of course, you want to get the usual Omen (or whichever threat meter your guild uses) and Deadly Boss Mods.