It is said that we can use a method called eye contact to approach a girl. However, if I approach a girl, I would smile. I think my smile may reflect my friendliness or weakness. My smile may convey the message, "Hi, I don't have courage to look at you, so I smile to ease my nervousness." Or when I look at a girl, she may think I'm horny. You may call it staring. So how can I practice so called eye contact? How to differentiate it from staring?