After having manuals all my life, I am actually looking forward to having my wife drive the M3. She can drive manual, but hasn't done so in a while and doesn't feel comfortable driving my 335i now. She doesn't want to mess it up.
I think common sense prevails and it's only fair to tell anyone driving a different car what things they should look out for. You can't expect everyone to know every car type inside and out.
So that being said these are the things we will most likely discuss:
1- Car rides low so watch curbs and speed bumps (take at an angle)
2- Park in spots away from high traffic and where only one side of the car is exposed to another car (prefer the other cars passenger side).
3- Keep the revs under 5500 until further notice/no M button (break in)
4- Skip any street parking for now
5- Have fun