Ahhhh, It would not be much of a secret if it was revealed!
seriously though, persistence and it depends on your country code. I have only seen two offers in 10 months and was able to snag one of them. I check every day. If I were to check more than that I would have to assume that I need to get a life. Much better chance at winning a contest than a power user product where I live. Good luck my friend.