Dude, I applaude your attempts to venture beyond you little
relationship bubble now. But the transition process is going to be
hell, well at least the way i know it. Look from my experience, the
new chick needs to know that you're already attached. It's not
possible for both girls to be kept in the dark. The new chick needs
to be willing to accept that she's going to be no. 2 for a while
but will eventually become the one. The whole processes is going to
involve months of lying through your teeth. Probably more lies than
you have ever told in your entire life. I've also accepted the fact
that it's also not entire possible to prevent your current gf from
becoming aware of no.2's presence. Let's face it she's going to
call, but a set of codes needs to be prearrange to let her know
when you are with no.1. You also have come up with some incredible
excuses on why this woman keeps calling. Do not store your new gf's
no. on your handphone, delete away every sms that she sents after
you read it. When you are sure enough about no.2, a clean break
would be the ideal situation between you and your current girl. But
more likely, her curiosity would have gotten the better of you by
then. Then, facing the music is part of the deal, you have to go
through with it. Have fun, hope this helps, good luck on your
venture. And to all women out that thinking of having a go at me,
go ahead, men are flirtatious by nature, we just wish women are
too. 
