Selfie is a natural sign. Simply hold up your dominant hand in front of you with the thumb and index finger sticking out. Then smile at it as if you were smiling at your phone camera, and bend your thumb and index finger in unison, as if you were snapping up some selfies.
Teach your toddler the selfie sign in the context of posing for a solo or group shot that you will post on your social networking accounts. Be wary though, of course, of posting your little ones' photos on the Internet! We all know too well what dangers are lurking online, so let's keep ourselves abreast with current news, and protect our children from online predators.
Teach this sign along with the other flash cards pertaining to SNS and related online activities.