/cast [modifier:alt, target=Focus] Hex
/cast [nomodifier, target=mouseover] Hex
all in one macro, you can take out the modifiers and use 2 separate macros, or just copy past that into 1 macro, Hold ALT to cast Hex on the Focus'd target, or don't hold alt to do it on the mouse over
This will cast it on your focus.
/cast [target=mouseover] hex
will cast on your mouseover. Replace with bind elemental and wind shear as appropriate.