For other noobish windows users like myself, you can simply dump the following into a bat file. When run, it'll look for a file called "scanThis.pdf" and apply the conversion with ImageMagick.
IF EXIST scanThis.pdf (magick convert -density 100 scanThis.pdf -colorspace gray +noise Gaussian -rotate 0.5 -depth 2 SCANNED.pdf) ELSE (ECHO File scanThis.pdf not found & PAUSE)
Nope that's it. The bat file here is just a clickable shortcut so you don't have to remember the whole command. The interesting stuff is happening in ImageMagick, which has to be installed already.
