You want to be using HealBot instead of clicking around trying to target players or clicking party frames.
HealBot is the best gift you can give yourself as a healer.

Make sure you set your Primary Stat to Spirit on the Ascension spec interface. If you think your spec is bad try out one of the premade builds people put up in the spec interface, theres a button there to look at builds and automatically load them onto your character.

Stack Spell Power and you should be on your way.