Backing up WD MB Live with WD MB Essential?


I am new to the external backup drive world and need help in learning the best way to manage my backups.  Here is the setup I am currently attempting to configure:

I have a WD My Book Live 2TB NAS drive that I want to use as a media storage device for the home.  I also want that drive to be the location for regular system backups of my 2 laptops I have at home (1 MacBook Air 1 Dell Inspiron Laptop running Win7).  I think I know how to setup the backups for the laptops, per the bundled software, no real concerns there.

The thing I am trying to do which I am not sure the best way to go about, is to use my other external WD My Book Essential (USB) drive as a backup drive to make a copy of my My Book Live NAS drive.  I want to have a redundant copy for safety (like a raid setup).  

Can anyone help me determine the best way to make that USB drive work as a backup of my NAS drive?  My thought was that I could use some kind of backup software on one of my laptops to backup ONLY my networked drive path to my connected USB when I manually decided to do a copy (like once a month).  I would plug in my USB drive and manually initiate a “backup” of just my networked drive, so it only copies over the new data from that NAS drive.

Kinda kludgy I know, but is one way I assumed I could create some safety for my data.  I wanted to use an online backup service (CrashPlan or BackBlaze) but am finding the costs for NAS drives way too extreme.  I also figure if I go the route I express above, I can use BackBlaze for $5/month and backup my PC with that USB drive plugged in and have even more security.  

If anyone can help me with the best way to approach this I would be very grateful.  My concerns about doing the backup of the NAS drive to USB drive is what software or how to do that.  As I said, I would be having my NAS back up my laptops routinely - so plugging in a USB drive and doing a different kind of “backup” is perplexing me.  Maybe I am over thinking and someone has a more straight forward approach.

Thanks so much!

Check page 85 of the manual.

Thanks Alucardx23,

however that helps if I have two Live drives, I am trying to backup to a USB Essentials drive attached to my PC.  Know of anyway to do that?  

My thought was I could run some kind of Backup software on my PC and just target my Live NAS drive as the destination to backup?

Thanks again.