My two biggies -

Rear brake under 5 MPH and when coming to a stop. Learn to stop with left foot down only to accomplish this.

No wiggling around at slow speeds or stops.

Ask before getting on, and before getting off.

Ok....that was 3.

 

First 3 things I used to tell passengers: Sit down, shut up, hang on. But seriously you'll have to figure some things out on your own. For example some are telling you to have the passenger lean into turns with you. I discouraged this. I found that they were anticipating and moving too soon or too late. I just had them stay centered and let me do the work.
I've seen passengers with friends who are waving their arms all over the place, turning at the waist back & forth and causing all kind of jerky movements. I also discouraged that.
As someone else mentioned, proper dress. I've had many women approach me over the years at stops asking for rides. But if they're wearing shorts, sandals, etc. then there's no way that's happening.
In the end, I bought my wife her own Deluxe a couple years before we were married. I joke with her that it's the best $10k I ever spent, to get her off the back of my bike.

 

Can't really add much to what has been suggested. You don't want to throw too much at her and get her freaked out before the first ride. One of the most important parts is the getting on and getting off. My wife always makes sure I am set before she gets on behind me. I firmly plant both feet, make sure the bike is straight, and hold the front brake no matter if we are on level ground or not. She steps on the left passenger board with her left foot and raises herself up over her seat and gets in position (starting to sound dirty). She gets off the same way while I hold the front break and she never gets off until I acknowledge that I am ready.


Of course last year all that went out the window when we bought our first Trike. Now she gets on first. She could fall over in her seat and unless I saw it in my mirror I probably wouldn't know it now!

 

Started giving rides to girls when I was a kid

Best advice I gave out was " HANG ON ..... tight "

 

I always tell a passenger that is riding with me for the first time to only get on and to dismount when I tell them to. I also tell them to never move around or adjust themselves when I am at a stop, going around a curve or when turning. That they have to keep their feet on the pegs and be still. There is plenty of time to make those adjustments when I am going in a straight line.

I tell them not to fight me or to try to "help" me steer or lean against me. Act like a sack of potatoes until you get used to us riding together.

Don't panic! If you are uncomfortable, calmly let me know and I will pull over as soon as we can safely do so.

Enjoy the ride.

 

And they have to be comfortable. In time, if they feel safe, you won't even know they're back there.

 

Not to get personal, but a RK is a heavy bike to begin with. If she is a "plus sized" girl, you better be very secure with your stops, go's and slow speed maneuvers. If you are not flat footed, and are not a strong guy, you better start working out. If you need to practice, consider putting a couple/few of 50lb bags of sand on the back seat and see how you feel. I hate riding with anyone on the back. Use to do it all the time on lighter bikes with 100lb girls, but no more.

Good luck.

 

All the points here have been spot on but I will add this. She needs to learn how to mount and dismount SMOOTHLY. its not a race but it has to be done quickly and smooth. Especially if she's a larger gal. The woman im dating now rides great, I can drag the floorboards and ride almost like normal. But she has a hard time lifting her leg up and over. Its such a clumsy mess and she will be the reason my bike hits the ground if she don't figure it out soon.

 

Passenger hand placement can sometimes be distracting.

 

Ask before getting on, and before getting off. Yep !!