I was informed that OSX Yosemite would be an asset to my computer. I do NOT like it. I would like it off but unable to find how to do this.
Presumably you didn't make a backup proper of the system "as was" prior to installing Yosemite? Isn't too hard to make an image that can be restored at any time. Carbon Copy Cloner being one software utility that allows it; and there are others... Always wise to make a backup of a system as is before 'upgrading' the OS to the next offering from Apple-land (or M$-land for that matter)... Meanwhile - the link from "grasshopper" is useful to follow...
None of these answered my question. Finally received help from a friend. Please do not send this to me again.