I guess I didn't explain the "lean with me and the bike" very well which is basically what everyone else said. The point is, she shouldn't try to counter-lean (lean in the opposite direction) of you or the bike. Being a rider herself, that shouldn't be an issue anyway.

 

Another thing that helps is when stopping, do it more quickly than you would when riding alone. It will make the stops smoother and less "wobbly." Be sure that she knows to sit still when taking off or stopping and if she has to adjust when you are sitting still to let you know.

Also, a good habit to get into is to always talk over the same shoulder (we used to always talk over my right shoulder).

 

I have her just sit and enjoy the ride.
At the beginnig she would occasionally lean forward over one side or the other while I was stopping. After one near dump and my choice words that followed she doesn't do it an more.

 

When you are just starting to ride 2-up you may want to go to an empty parking lot for the first trial ride or two. Falling over in traffic would be embarrasing. Go over the dos and don'ts before you start and then see how it works for ya. For example, tell her to NOT put her foot down when you stop - if she does anyway you know you need to work on things before you get out in traffic.

Most importantly, in order for your passenger to make you as comfortable as possible ("which should make the ride safer" - you may want to quote these words) she should never wear a bra and she should have big ***** to lean back on. I offered this suggestion to my wife but apparently there are some rules she is willing to ignore. <G>