I'm confident in my abilities regarding where to place and not place hyphens except in one area: when you have a phrase that consists of a noun and a noun that consists of a verb with -er at the end, does that get a hyphen?
For instance, if I'm talking about a scheme that will give you twice as much money as you had before, is that a "money doubler" or is it a "money-doubler"? Some instances of this sort of phrase just turn it into one word like "heartbreaker" or "homemaker."
I have no idea what to call this, so I don't know what to Google. Any help would be greatly appreciated.