If you use FCPX as frequently as I do, you'll want a leg up on the new features. The interface is quite different! Take advantage of the free assistance here. Multiple instructional videos within.
Later: Rats. I have to update to Sierra to get a hold of the latest version. I can upgrade on my MacBook, but not my iMac yet. (sigh) Time to buy another drive, do a clone, and get the old girl up to speed.