We did a kara run few days ago. We saw we lacked communicative there and maybe a bit gearwise aswell. So my suggestion is to gear up and find information about Attumen the Huntsman etc. U can find allot about them on www.wowhead.com and thottbot.com.
Also another suggestion was to do instances with pre fixed groups. so u have 5 chars playing with eachother allot so we can get some kind of chemistry together.
If you have any toughts about this please leave a comment.
Oh and make sure u get a microphone so we can use this ingame. If ingame doesnt work properly i will try and get us some kind of ventrilo or teamspeak.