To complete the study, women—some professional actors and some volunteers—were asked to mimic the flirting expression they would use at a bar or on a date to get attention from someone they were interested in. The study used the Facial Action Coding System (FACS) to identify the morphology of the facial expression that was identified by most, if not all, of the men on the receiving end as flirting. This flirtatious facial expression included “a head turned to one side and tilted down slightly, a slight smile, and eyes turned forward (toward the implied target),” according to the study. This specific non-verbal communication was consistently used by women to display flirting, and men consistently picked up the cue, making it the easiest way to get your point across without saying anything. “Our findings support the role of flirtatious expression in communication and mating initiation,” co-author of the study Omri Gillath, PhD, said in a statement. “For the first time, not only were we able to isolate and identify the expressions that represent flirting, but we were also able to reveal their function—to activate associations related with relationships and sex.” RELATED: For more up-to-date information, sign up for our daily newsletter. The study marks the beginning of research into the science behind flirting. “There are very few scientific articles out there that have systematically studied this well-known phenomenon,” Gillath said.ae0fcc31ae342fd3a1346ebb1f342fcb According to Gillath, this study was the first to pinpoint a specific facial expression and test its effects. These results help draw a roadmap for clueless flirters by helping them identify a more concrete way to demonstrate and understand desire. And to boost your appeal to potential mates, This Is the Easiest Way to Make Yourself More Attractive, Study Says.