thats probably a decent gist of it
granted there is a lot of variety you can play with on him how early you feel comfortable putting a point in the off skill of your build to adequately use his whole set of skills and certainly item builds (when or if to get aghs for example, i get it because i have poor skill management, but if you can keep a calm head and use your skills well you really shouldnt need it unless youre trying to get on a xx420invokerplayzxx youtube video)
a lot of players underestimate his right click and forget to use it outside of an occasional cold snap kill, but generally in fights he can just right click almost as well as any other semi carry (well depending on your e and w)
skill management is super important as invoke has a shit cooldown for so long, so you have to think like 30 seconds ahead and know what you need to have a third skill able to invoke when you get there
dont waste your spells on stupid shit early or else youll be going back to base a lot (unneeded sunstrikes or random tornadoes/meteors to clear creepwaves etc)
for qe the skill pattern is first skill q or e (defensive or aggressive in lane? are they ranged and going to bully you? or do you want to last hit better and youll be fine?) than the other, than an invoke (a lot of this can be shuffled around depending on how comfortable you are with him, and when you watch pro players on him you'll notice they all have little quirks they do differently) then you just get 4 e and 4 q to get your two forge spirits where you stop leveling q max e, get some w, run around like an asshole kill things
practice
's, practice last hits so you know how to do it with him
also just spam shit like in sc2 for max apms... i mean not really but when youre not actually attacking to get a last hit you should be 3 q for regen instantly 3 e for a quick attack and then back to 3 q, practice that and you get good regen and high damage for bully or last hit, its like tread switching you just need to practice
the stuff about knowing how to actually invoke yeah thats important but whatever that takes like 10 mins of learning
edit dreams post gud too