How can I turn my short story into a novel?

I just wrote last week about Sleeping Beauty but a different version of it. (I changed the characters, and the conflict, and mostly everything except the fact that one of the main characters is cursed and must fall asleep, only to be woken by true love's kiss. In this case I made it the guy.)

I want to turn it into a novel, except whenever I try to write novels I get intimidated and I can't seem to do it. But then again, I've never wrote a short story about it beforehand.

What I have to do to turn it into a novel? Obviously, I need to add more detail. But do I add more characters? (There are only 4 in my short story.) Do I make the scenes longer? etc.