Help me write batch file to duplicate displays by default

[mikesworkbench]

I need my Windows 8 computer to stay on duplicate display all day long by default. It keeps reverting to extend. I'm a teacher and I'm showing powerpoints and pdfs all day long and it is annoying to hit the alt F8 key all day long to switch back to duplicate. Any simple solution? I can't find one.

Looking around it looks like at batch file could be written to make duplicate stay as the default... problem is I've never written an batch file but would like to if someone could walk me through it. It looks like the batch file needs to include: DisplaySwitch.exe /clone

I'm not sure how to write the batch file or where to save it to once it is written.

Any help to my problem would be appreciated.