Hey,
I know where you're coming from, everyone probably does, I've had a lot of problems with AA as well and I'm still working on it. While I have a few tips I'll share in a moment, the most important thing I've learned is that in order to approach comfortably and without hesitation, you have to become the kind of person who always talk to everyone, everywhere. That's girls, guys, old people, kids, on the bus, in the mall, at a bar, whatever. So I simple practice talking to people in the every day.
This is making a huge difference for me at the moment. I'm committing myself to "approaching" 5 strangers each day, even if it's just asking what time it is. In my case it didn't take more than 2 days before I become A LOT more comfortable talking to strangers and keeping the conversation going.
This has also taught me something else. "Warming up" has a huge effect, with each approach I do during the day, the next on becomes increasingly easier. I do this when going out at night too now, just asking people simple questions, compliment a cool t-shirt or whatever. It get's my social-muscle going and makes later approaches so much more easy for me.
Last thing, for day-game, come up with some fall-back lines. This helps me honor the 3-second rule immensely as I know I always have something to fall back on if I don't know what to say.
I hope that helps, good luck
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