Ive been reading lots of the forum and e books and have started putting some to use but i dont quite get the way to put a false time constraint into your opener...

is it: Hey, can i get your opinion on something do men or women lie more? i have get back to my friends in a minute...

or do you say the false time constraint in the middle like:

hey, i have to get back to my friends in a minute but can i get your opinion... etc...

help is appreciated

The best way to add in a time constraint is just to naturally slip it in there. You're on the right track with the "i need to get back to my friends in a minute" idea but you dont even need to be that specific. Something as little as "hey, i only have a minute and i need a female opinion on ______"works. Just remember two key points. The time constraint should be mentioned within the first 30 seconds of approaching the group, that way they don't make the assumption that you will be there all night. Second, show the time constraint in your body language. If you are holding keys, facing slightly away from the group, leaning backwards, or even talking as you are walking off, this will reinforce the idea that you are not going to be staying long and will make them more comfortable with your presence. Hopefully that helps.

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"If your not living on the edge, you're taking up too much space."

I feel its best to drop it before i ask the question. Something like 'i've only got a minute/gotta get back to my friends but i need your opinion on something first'. Its sounds odd asking the question and then saying i've gotta go in a sec. Now i never open by saying 'i need your opinion on something'. I open with something situational or direct and then ask for their opinion. I've found it works better this way. I try to use material that sounds more natural and stuff i feel comfortable using.