I made these up the other day so they are recent. I use them as kneeboard images.
Extract the attached zip file into your "<user>\Saved Games\DCS" folder. It will put a "kneeboard" folder into your "<user>\Saved Games\DCS" folder with a bunch of jpgs that have all the latest hotkeys. Now while you are flying you could hold the "k" key down and press the "[" key to review them while in flight. If you don't want to hold the "k" key down you could press "Rshift-k", this keeps your kneeboard on screen, and use the "[" key to view the hotkeys. KNEEBOARD.zip