When laying with a significant other or a person of interest, you begin spelling words and letters on their skin with your fingertips, often followed by the individual trying to guess what you are spelling.
Boyfriend: *Using fingertips on her back to spell* "I L O V E Y O U."
Girlfriend: "I love you, too. I love when you write me Fingertip Love Notes."
when you're holding up your phone and making faces at it, as though you are taking a selfie, but you're really taking a picture of the person across from you or the wall or anything else that seems interesting but you don't want to be caught dead taking a picture of.
This action is often made more convincing by wiggling the eyebrows or opening the mouth, to pretend you're trying to get a Snapchat filter to work.