As the others have mentioned, the game already has an autosave feature - it autosaves every time you sleep. You can find it in the "LOAD" page; just click on the "A" at the bottom next to the page numbers :)
Tyvm. Also I have to say, I am thoroughly enjoying the game so far! The writing and pacing are both fantastic, and that along with the element of mystery are keeping me more than hooked - I'm enthralled. :O
