1) Call whoever you think is going to die by the end of the series. In addition, if you want you can reverse it and also call someone who is already dead ending up alive at the end of the series. I know death is a bit fuzzy right now - to simplify, I'm saying Claire, Christian, Charlotte and Locke are currently dead, but Jacob, and Juliet are alive.
2) Call any other face or heel turns. I know "face" and "heel" is a bit fuzzy also - to simplify, right now I'm saying Ben, Jacob's Nemisis, and Widmore are heels, and the rest of the major characters are faces.
3) Call any hookups that happen over the season
4) Make one random prediction about whatever.
5) Make one major prediction - namely "what the heck is it all about?"
Scoring: one point for predicting each correct death/resurrection, face/heel turn, and hookup. Minus one point for each incorrect prediction.
Plus two points for getting the random prediction right - no penalty for getting it wrong.
Plus five points for getting the major prediction right - no penalty for getting it wrong.
End up dead - Sawyer, Penny, and Widmore, End up alive - Jacob Hookup - I kind of have no idea how this will manage to happen, but I'm saying Naomi and Sayeed somehow manage to kick it. Face turn - none Heel turn - Faraday's Mom, Rousseau.
Random prediction - at some point in the season we see Richard Alpert looking a different age.
What's it all about? Jesus - I really have no idea. I'll say the island has some fundamental universal truth that Jacob is trying to spread to humanity and Nemesis thinks humanity isn't worthy of.
End up dead - Ben, Sayid End up alive - Faraday, Locke Hookup - None Face turn - Ben (will have a redeeming, self sacrifice that leads to his death), Jacob's Nemesis Heel turn - Faraday's mother, Jacob
Random prediction - The show ends with every main characters dying, and Jacob and his nemesis having a very similar conversation to the one they had to open The Incident as we see some ship/plane making its way to the island.
I think the point is that the Daily Doubles tend to be in the $600 - $1000 range. So getting them taken care of early eliminates the chance for someone to make a big jump later in the game. If you only have $1000, the most you can win is $1000.