I suggest giving it to her from both ends, i.e. one in the mouth and one in the pussy. Switching off would probably be the most fun. This is usually how threesomes start before you get into the complicated stuff. lol.

What I did one time before we took the plunge was I purchased numerous dildos(life like ones) of various lengths and girth and hid them in my car. Took her to a hotel got her a little worked up and asked her if i could play a little game and tied her up. I put a blindfold on her played with her really getting her worked up. I then put a vibrater in her held in by a pair of panties and told her i would be back in a little bit that i had a suprise for her. I came back with the toys and put on some music near her head. I had her tied face down on an ottoman. What a lovely sight. I then kept going to the door like more people were coming in. I then knelt behind her in a pair of jockey briefs and put myself in her after taking the vibrator out. Did her for a couple of minutes and then i put the different size toy in my briefs and did her with them. She ended up cuming gallons dripping on the floor.Sometimes I would kneel at her side put myself in her mouth and use a longer one on her pussy. She would cum so hard then. That is how I finally talked her into it becuse her body let us knoww that she was ready. Let me know what you think.

One with you at her side with your dick in her mouth or on her tit while she takes that BB toy. Maybe a little cum on her titty with it in her. How about you fill her up and then put that BB toy in her. That would look like that BB toy did it. You could always let me photo so it would easier. Now that would look hot, her holding both our cocks and the BB toy in side her.