Quote:
Is there a general rule about when to ask for a phone #?
Cheers!!!

You don't ask for a phone#! Why, because then you become needy in the eyes of the HB.
AFC
ask/beg for phonenumbers,
PUA
gets phonenumbers
When you game a girl, opener/routine, and the social hook point is found. The girl likes to talk to you, and you have good game. You kino some, she kino's back. You feel that this is going well (calibrate). Then it is time to use a false time-constraint
[
'I have got to go'. Thank you for such a nice conversation. I feel comfortable talking to you. I have so many things to tell you, and I want to hear more about your hobby. How can we continue this? ']
Now, if you gamed well, the girl will offer to give her number to you

[
'I can give you my number, if you want'] Letting her give you her number will have two advantages:
1. DHV for you! You are not needy, and she is the one who is giving her number.
2. When you call her, the responsiveness is much higher then when you asked her number
Good luck!
ps: sometimes the girl hesitates, you should help her. [
'I don't use FB. Yeah, i know, I am old-fashioned. I only have a pre-paid phone 
]
If she still hesitates to give her number, FB is ok. It is not about the number, it is all about the next opportunity to meet, the medium doesn't matter
