Dan Tamarkin here from Tamarkin Camera
This to show you how to unload your Lecia M series camera. This video will be helpful for just about any Leica camera that there is in one way or another. This is a Leica m6, and it has many of the same features of the M4, M4P, M4-2, M7, MP and onward. There's a more similarities than there are differences.
The first thing to do once you're done with your roll of film- take the rewind lever, move it down, flip up the rewind lever, and start cranking away. You'll feel the film come off of the spool. Once you're sure that it's off of the spool, open up your baseplate, being mindful of the little hinge fixture on the other side, and voila! Off to processing or off to the darkroom for you!
The camera knows, mechanically, that it's in the rewind position, No need to move the lever back. Just complete winding the camera and voila! Ready for another roll.