On my newest computer, I have twin SSDs for Windows and My Documents, and twin 1TB drives for everything else. I simply clone 1 SSD to the other, and remove the original C: and put it in a case, and move the clone to where C: was. The same technique is done on the 1TB drives. All are on slide-in bays, so it's only 10 seconds or so to insert/remove/swap as needed. I make SSD backups/swaps weekly, and 1TB backups when I've finished working on a 'project' and want it off my SSDs.
I also have a 1TB USB external drive for offsite storage. I used to keep my offsite storage in my desk drawer, but in my current job, I don't have a desk of my own, so I store it in a cabinet at church, and my pastor knows that all my church pictures, etc, are on that drive, in case I am no longer able to serve. I simply clone the 'current' 1TB in the computer to the external drive, about once a month or so.
Until I have a project on the external drive, I carry a full copy of the project (RAW, and in-process versions) in my pocket on one or more 16mb flash drives! I'm always concerned that I may come home to an empty house, a ransacked house, or a burned down one. Living in Massachusetts, I also expected one of my two big hollowed-out-by-rot maple trees to come down this week...perhaps on my house. Needless to say, I spent Sunday making backups and getting the offsite drive back to church. Fortunately, we got off VERY easy from Sandy.