Creepy is usually when there is incongruence between things you say and do. So for example, when a guy says he wants to be friends but then starts hitting on a girl that's creepy. But if that same guy was upfront about his intentions, it wouldnt be creepy

Creepy can also mean a complete lack of tact and social intelligence. But generally, you can really minimize it by being upfront and straightforward, and most importantly unapologetic