Classic How to make/use mouseover macro for incorporeal?

I play ret. I have never used, or even really understood, mouseover macros. How would I set up a macro for incorporeal? Ideally, it would cast turn evil, and if turn evil is on CD then it would cast repentance. That way I could use it for both incorporeals, and it would just end up using both spells. Is this feasible? And how would I get it to not accidentally cast on some other mob if I happen to mouse over a different mob or click one? Maybe these are dumb questions, but I really don't know the first thing about this type of macro. via /r/wow https://ift.tt/DmOabWQ