An easy way for the average Joe is to get to simply get some backup software, like SyncBack. Set up the directories in which you'd like to copy files and save them, and set the schedule on how often you'd like it to run. The schedule can be ran anywhere from seconds, to days. You also can also password protect the backup automatically within the Syncback advanced settings.
I have a backup running every 15 minutes of my wallet.dat, and that is saved to my Dropbox after being compressed and password protected. If the amount in my wallet hasn't changed, the backup doesn't do a thing. Dropbox keeps a record of all changes of your files within the last 30 days (FOREVER for payed users). If anything goes wrong within the month, I have a record of nearly every change that's happened this month.
I could even run this backup every few seconds to check for changes if I wanted to, but no need for overkill.
Shameless plug here, but if you don't already have dropbox and what an extra 250mb storage, follow the referral: http://www.dropbox.com/referrals/NTEwNzcxMDc5OQ
Fair warning, I think I'm able to see the e-mail addresses that sign up with my referral, so if that's a problem, don't use the referral.