I don't mean from cable rub; just the places on the frame that are prone to getting scratched (ie. underneath the downtube, sides of the the top tube, etc.). I just use electrical tape on my bike since it's black. Keeps my frame looking as good as the day I bought it.
Couldn't you just find some touch up paint at Canadian Tire? Or maybe this time use some electrical tape or clear vinyl tape to protect the frame so it doesn't end up so scratched and beat up.