It is extremely helpful to have your common tasks sequenced to execute through a typical series of casts all in one macro/button. As an example, my petattack macro on the locks looks something like this:

/assist focus
/stopmacro [flying]
/dismount
/petdefensive
/stopmacro [help] [noexists] [dead]
/petattack

...and on the priest, that same key is:

/stopmacro [flying]
/dismount
/cast Power Word: Shield
/stopmacro [help] [noexists] [dead]
/script SetRaidTarget("target",7);

You get the idea. Having your heals sequenced is often good as well, especially if you're running the healer as a follower account. Macros such as this help condense your healing tasks:

/castsequence [target=targettarget] reset=12/combat power word: shield, renew, greater heal, greater heal, greater heal