First, convert your files to QRs on the website, http://smileboom.com/special/ptcm2/qrmaker/en_us/qrmaker.html.
Use the snipping tool, search it in the start menu. Use rectangle select and select the QRs. When you are finished, push CTRL + S to save and DONE!
Alternatively for Windows, scroll down if possible to hide the above information, make sure the browser window is in focus, and press Alt + PrintScr. Open Paint or a similar program, paste it in, crop to remove unnecessary information, and save.
On Mac, hold Cmd + Shift + 4, then click and drag to screenshot the QRs on your screen. It should save to your desktop. Rename the file, and they're ready for uploading.
For Linux machines, PrintScr should work similarly as it does for Windows.
Many Linux distributions should also come with screenshotting programs preinstalled.
Don't comment about already knowing this. Why are you reading this then? Whatever. Hope it helped!