You really can't force 3-ways, they happen naturally if everyone is willing. So, to pick up a 3rd person, don't try to force it as "hooking up a 3-way". Instead, go about it as picking up any woman, and have your gf join in once it's a go. I've found that nearly any woman will go 2 on 1 with a guy, or take 2 guys on. But guys won't do 2 on 1girl nearly as readily. Face it, women are hot, hairy dudes are gross. So, pick up a woman and go about it like any new f-close. Or, have your gf pick up a woman from a gay bar like it was a lesbian pick up and you were the "sex toy". Your odds are far better at a gay bar. Lots of straight or bi women hang there, and their minds are in the gutter anyway... donno why... just a more sexual frame.
If you got the green light for a 3-way, don't wait for your gf to give the approval. If you are getting IOI's, act on them-even as far as make out with her, then ask your gf: "She's into me, what do you think?" If your gf resists, point out past failures were due to lack of interest, etc. She'll likely accept any girl you do - you know her tastes.
As far as how to's, I have a few things tips for you.
1. Do not mention your intent to have a 3-way, or your girlfriend, to the new recruit. In fact, so much as the 3rd person should know, it's just another chick in the same position as her. If you mention "this is my girlfriend, we're hooking up a 3-way with you." The 3rd girl will freak out and bolt, it's the whole "slvt defense" thing.
2. Go about seducing the 3rd person alone. As always, isolation is key. Then, have your girlfriend arrive on the scene to join in the fun. Better your gf come in later than sooner - this will give you plenty of time to get the 3rd person aroused. More arousal = less hesitance/resistance.
3. THIS IS CRUCIAL: When your girlfriend "interrupts you", do not act suprised. The 3rd person will pick up on the nervous vibe and mirror it. If you act like it's a hot scene and everyone is welcome and it's comfortable and safe, then the 3rd person will go with the flow.
You and 3rd chick making out in bedroom. Your girl comes in. You: "Hey, (gf's name), this is (3rd girl's name)." "(3rd girl), this is (gf's name)." Then go back to making out with the 3rd girl like there was never an interruption or cause to be nervous.
4. It's up your gf to get in the mix on her own. Your role from the start is instigator and crowd control. There is only one person there who is going to potentially have a problem with the scene, so, she get's all the attention until it's obvious that she's getting into it. (kissing your gf, letting your gf take off her clothes, taking off your clothes, etc.)
5. Less is more. Shut the fvck up and make with the sex. "Hey, wait a minute! We need to talk." "Or not." - Make with the sexin'. "No seriously..." Don't answer, instead, start making out with your gf. If she insists, she may want to lay out some rules like "I don't do girls." Then answer with "Is it okay to get done by girls?" "I guess, maybe." "Hey, go with whatever feels best, you don't HAVE to do anything you don't want to, we're here for pleasin' not stressin'." Then get back to the making out.
Just like any other pick up, you will get some rejections. But confidence is huge, assume the sale. Here's the attitude to have: "Hey, my gf and I will be sexin'. Not interested? Get the door on the way out."
I had a woman get upset and leave the bedroom, only to come back in later. Why? Because she was sitting in the living room, half worked up, listening to my gf's orgasmic moaning and screaming while she was getting nothing.
Good luck. Don't TRY to hard.
