Something I have to say from the start:
If I immediately like a guy, he can be shy, expressive, or aggressive - it doesn't matter - because I like him I am open to anything he says or does.
If I immediately don't like a guy, he can be shy, expressive, or aggressive - it doesn't matter - because I don't like him I won't be open to anything he says or does.
This may sound confusing, and it is to a degree, but I'm hoping other women know what I'm saying. I don't know that I've discussed this before, but with me, the same 'line' can come out of two different guys and with one guy - the guy I like - I think he is the funniest, smartest, sexiest guy, but when it's said by the guy - who I don't like - I think he's trite, dull, and unsexy.
You got to Be, Do, and Say what feels natural for you. Some women will think you're the greatest, others won't.
And how do I "immediately" like or not like a guy?
Beats me how it works.