I am not sure why mana is such a huge problem with me since the release of cata.
I've got the best gear I can get for what I am doing and the amount I play. However, in heroics, I go oom about every pull. Basically, the only time this doesn't happen is when the tank is the only one taking heavy damage.
I'm not a bad healer- I just go out of mana quickly. I've been removed from a group because of it and insulted a few times. It's irritating.
Could someone please take a look at what I've got set up and let me know what I could be doing differently?
Enchant a few more peices of your gear. Reforge your Mastery Trinket ( The Blood of Isslet) to spirit it will give you +100 spirit. Get Heartsong for your weapon enchant.
Prep for every fight... get 3 Holy power by pre-shocking party members.
Use hand of sacrifice on the TANK... you'll never notice the damage as you heal yourself by healing others.
Judge every chance you get.
Use Aura Mastery with either Resistance or Devotion to help with certain damage types.
My main spells are Holy Shock, Holy Light and WoG. I use Divine Light if the tanks HP is steady and he needs a big heal. Flash is used for the bigger quick heal if lots are taking damage. Use Radience and LoD where needed and when it is efficent. UNSPEC FROM BLESSED LIFE
... put those 2 points in Crusade. Makes you Shock better and 300% better Holy Lights after a mob dies.. awesome for trash.
The 2 points in Paragon is fine, but I like Improved Judgement better. The range is awesome for keeping you mana up as you move.
Doing all the above stuff should make you experience at healing go a long way.