How to play Planning Poker

Planning Poker is a game which help us to do planning in Scrum. We can use it for adding the weight to the user stories.
Ok this is how it is played..
1. Scrum master get ready with the Planning Poker card pack for each member of the team who participate this session
a. Those cards should have numbers such as 0,1/2 ,1,2,3,5,8,13,20,40,100. (Why these numbers ? Let me find out and tell you .. : )
b. Write the Numbers large so it is visible when needed.
2. Appoint a moderator (Can be anybody)
3. Ask the Product Owner to come to the Session ( He doesn't play Poker)
4. Moderate Read out the 1st User story
5. Team members question the Product Owner about the story and Product owner answer them
6. After all questions are answered, each estimator privately selects a card representing his or her estimate.
7. When everybody is ready all the members put selected card to the table.
8. There can be major variations., one member may have selected 2 while the other person has selected 5
9. Then they give reasons for selecting those numbers. One may think there is some additional research needed to perform the task., another may have thought much more easier way to do that task
10. Once all these points are discussed and asked the questions from the product owner, again the team play the Poker - This time its expected it to be more similar numbers
11. Of the numbers are not quite satisfactory it goes through another round. In normally you play the game for 2 rounds per story point. But there is no rule for that.
12. In last round if everybody comes with 3 and only one person comes with 5., we ask him or her whether she is agreeable to estimate the weight points as 3. If she agrees , we have no issue., if she doesn't agree we need to listen to the reasons.
i. Planning Poker brings Multiple experts opinion to the table
ii. It has the team buy in for the final decision
iii. Averaging Individual estimates lead to better results
iv. Its more fun than just traditional project estimation by Project Managers and few senior members of the team

- This idea is extracted from Mike Cohn's Agile estimation and planning.