You should check the millions of lottery websites that exist and ask yourself: can I do something different, can I add some exiting feature?

You would need a system which proves you are picking it at random and place money in escrow.

Can't believe I won the first prize   Thanks

But even I won the biggest prize, it seems I still cannot withdraw anything   Look like I must win the first prize at least twice before I can withdraw. Sounds not good enough

Anyway, I've updated my post for the round 2

You got a cool idea here.

If you want something professional, feel free to PM me... only if serious

Step 1.  Participate in discussions on this forum regularly for 1 to 2 years.  Contribute usefully to discussions and demonstrate over this period of time that you are intelligent, even tempered, and fair.

Step 2. During this 1 to 2 years time, engage in transactions, and build a reputation as a reliable, honest, trustworthy individual.  Assist others with no benefit to yourself, but simply because it is the right thing to do.  Demonstrate a strong sense of morality and ethics.

Step 3. Learn to use PGP for encrypted communications with those that desire it. Learn to use PGP to provide and verify digital signatures.

Step 4. Consider all the things that might go wrong in a transaction, and structure your standard escrow agreement to account for as many of those possible issues as you can.  This way there will be no surprises or frustrations with the way that you handle the settling of disputes.

Step 5. Get a second computer to run Armory offline.  Learn to generate and use paper wallets offline in a safe and secure manner.  Hold all escrows in paper wallets stored in a secure location with backups so you will never risk losing your customer's bitcoins to theft or hardware failure.

Step 6. Do it for the benefit of the community, and not because you believe it will bring a profit.  In the past month, I've spent more than 20 hours handling over a dozen escrows for a total profit of $0.78 for the month.  There are much better ways to make money.  There are several very trusted people in this forum that already provide escrow either for free or for very cheap prices.  Nobody is going to want to pay more money to a less trusted person. Those of us that do it, do it because we don't like to see newbies getting scammed or shut out of potential transactions due to lack of trust.  We feel that providing a safe and secure business environment here at bitcointalk benefits the entire community.

Step 7. Create a new thread announcing your willingness to offer escrow services. Add a link to your announcement thread to your forum signature. Mention your willingness to the two most commonly used escrow lists on the forum. Wait and see if you are as trusted as you think you are.

Step 8. Provide your customers with information on how to contact you outside of the forum so they can complete the transaction if the forum goes down or disappears for some reason.