Pass a genuine smile when the person you are trying to flirt with through your eyes looks at you. Make the smile reach your eyes. People who are happy come off as more attractive. Smiling just as your crush or beloved looks in your eyes will make them think of themselves as the reason for your smile.
If you are a female, work on beautifying your eyes. Apply eyeliner, curl your lashes and apply mascara on them. You want your eyes to be looking great when they make contact with the person you intend to flirt with.
Nothing sends a clear message than the batting of the eyes a few times during an eye contact. Curled lashes with mascara on them will make the batting of eyes even cuter and serve to send out a clearer signal.
Stay confident during eye contact. While some people love shyness, it may prove to be a turn-off for others. It will not take you long to learn if the person you trying to make a flirty eye contact with prefers a shy person or a bold and confident one. Observe carefully as you will definitely get a sign.
Do not stare in the eyes of the other person. You are looking to make a flirtatious eye contact, not creep the other person out. Staring in someone’s eyes can make the latter feel awkward.