Odd question, but I can't think of anyone else who might have an answer: when you put sheets on your bed, do you put the sheet "wrong side" up, so if you were to fold it over, the "right side" would be showing? My mother taught me to make it like that and I've been doing it that way my whole life, but my roommates always looked at me funny
If you tend to fold your top sheet over your comforter, then wrong side up. If not, right side up. I tend to go for maximum sleep comfort, so whichever side is softer goes on the inside, looks be damned.