Intense eye contact............ Is that an ironic thing to say given the nature of this forum?
Seriously though, I think generally a lot of flirting is just an extention of normal sociability... Which might be difficult for an individual on the autism spectrum.
Finding random excuses to break the touch barrier is good, especially slightly teasing in jest (poking them in the arm/chest, patting them on the head etc)
And yeah I'd agree with above poster, laugh with them and be interested. Ask questions. Listen twice as much as you talk.
I'd also say, and this may or may not be easier said than done; be frank, and honest. Some may dissagree but I've found it works better for me.
And that way you won't have any misunderstandings and are less likely to get yourself into situations you'd rather not be in which is especially important as you're only 14.
(I flirt way too much with anyone I vaguely like, it's just about the only thing I don't have trouble with )
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AQ; 33
Aspie Quiz; Your Aspie score: 146 of 200
Your neurotypical (non-autistic) score: 61 of 200
You are very likely an Aspie