I'll let BMW explain about the procedure - I'm providing it here as a service to other owners.
Simple enough? The key is the having the lights ON to absorb any surges before the electronics do. If you have a small battery in the trunk, DON'T JUMPSTART FROM THAT. It's for accessories only.
To make it really clear, here is the jumpstart point on my 735i - remember, the (main) battery is UNDER THE BACK SEAT.