Nude selfies (nudies? nelfies?) are serious business.
Erika Moen of the wonderful educational adult webcomic Oh Joy Sex Toy has a comic tutorial at Medium. The tl;dr: The exchange of nude jpegs is for consenting adults only, and if you do it, do it with the knowledge that the image you share could end up being seen by anyone and everyone in the entire world. So make 'em hot. Or, seriously: you can abstain.