Drop and drag. My computer, click on your C: drive. A box will open. Make it half the screen. My computer again. Click on the drive letter for the external. Make that drive box half the screen. Put them side by side. Now you go to C: and click into the folder you want to copy. Click the folder (once) to highlight it. With mouse over that folder, right click, choose COPY. Bring mouse to external drive box. Choose what folder you want to drop it in or RIGHT CLICK and make a new folder. Open that folder and RIGHT CLICK in that folder and choose PASTE
This you have to do every time for each folder, every week or whenever. When you do it the second time. When you paste you will get a statement that "ddddd" folder already exists. Do you want to replace it? You will say yes- Then you will get a message "file (dddd) already exists. Do you want to replace it" You have to choose, "replace all". You will then have to wait while it, again, copies every single file in that folder. Each time, every time. That's why they made backup software.
Easier way. Download Freebyte (totally free). Make a folder name on your external. (or use one already on your drive) Choose files or folder with "ADD" and then destination (at bottom) is where on external you want your copy. Click ACTION tab. Start. You'll see what's up and any error. No timed backup, very small program, very fast as the second time you backup. It will only copy the newest files! I check and copy in 3 min. some 23,000 files at work with this simple program. There are other free backup programs you can use besides the supplied software. The Maxtor is just an external drive letter to the PC. Just like any memory stick. If you want to copy and paste... that will work too. My backups with my chosen software takes 15 min. to complete. And most of that time is checking if the file is newer. If I were to copy and past, it would take hours recopying all the files.