I'm not an experienced PUA at all, but I used this opener with success a couple of times now:
Hi can I have your female opinion real quick? Me and my friend back there have a discussion about whether or not I should dye my hair blonde. I think it would be cool be he says it will make me look gay.
The girls tell me not to dye my hair blablabla then I neg one by asking 'well you dyed your hair too right?', even though she clearly hasn't.
So far for the opener. What's next? Where to take the conversation after this?