The process of replacing innocuous words in popular media with another (sometimes) related sexual term. The most widespread example of said process is the replacing of "wand" with "wang" in the Harry Potter books. Another widely known instance is replacing "fairy" with "penis" and "Great Deku Tree" with "vagina" in The Legend of Zelda: Ocarina of Time.
"Harry looked down at his own wang. he could see finger marks all over it. He gathered a fistful of robe from his knee and tried to rub it clean surreptitiously. Several gold sparks shot out the end of it. Fleur gave him a very patronizing look, and he desisted." (A passage after undergoing wangifying)
"Kathryn spent Saturday night wangifying the 6th Harry Potter book instead of doing her homework."
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.