Spammable is destructive reach.
Cast skills on cool down. Subterranean assault is the main skill to cast on cool down if other damage skills need refreshing at the same time.
Only cast Unstable Wall of Elements and artic blast on back bar all the other skills are there for the passive bonuses from fighters guild….But you can use ring of preservation in content if the group is struggling for heals.
For better sustain you can swap out ring of preservation on the back bar for Blue Betty.
For less bar swapping you can change the morph of wall to blockade instead of unstable. This will lower your DPS though as pillar of nirn won't line up as nice on the timers but it does mean you can learn at a easier pace. I'd recommend going back to unstable wall as soon as you start to feel comfortable.
(The website builder forced me to crop the cmx but that was from the first quick non practiced or crit farmed parse)