My advise would be the opposite of what the above poster said, having clique has freed up a lot of keybinds for me so that I can bind them to shackle undead, stoneform, etc.
I prioritise "Oh shit I need this to be available if something goes wrong" spells to be the easiest to access.
Examples:
§ (The button to the left of "1") = Psychic Scream
1 = Desperate Prayer
(Human/Dwarf Racial Class Skill that instantly self heals you for 0 mana) 2 = Holy Fire
(Mana efficient damage, I usually open with this)3 = Smite
(Sometimes you just have to smite 'em!)4 = Mind Blast
(Not mana efficient but good when you need some burst damage)Q = Stoneform
(Increased armour, removes disease/bleed/poison)E = Wand "Shoot"
(my go-to damaging move)F = Drink (Will change to mount later)
Mousebutton 3 = Shadow Word: Pain
Mousebutton 4 = Shackle Undead
(Questing in Duskwood, in case you pull too many)Mousebutton 5 = Fear Ward
(Dwarf Racial Class Skill)Note that these are just
some examples of my keybinds and they are currently used for leveling.
For most of my healing and support spells I use the clique addon, it's really simple to set up and easy to use!
(It's kind of like healbot but it works for "most" unitframes (you assign click-combinations to use different spells when clicked on a unit frame).
Here is a
link to what my my UI looks like (somewhat out-dated).
The green numbers on the buttons are an estimate of how many times I can cast that spell until I run out of mana (Desperate prayer on button
1 being the exception since it doesn't cost any mana).
The red numbers estimate how much damage that spell would do to your current target (targeting stitches was probably not a good thing for this example).
I don't know exactly what addon it is that enables you to do this, but I think it is theorycraft.
I guess it's just down to personal preference.