The first step is to ask a question that you want confirmed. To encourage others to answer, you can offer a reward that goes to whomever gives the final answer. (You can also leave the reward as zero if you plan to supply the answer yourself and assume it will survive challenges.)
The opening date is when answers can first be posted. If the event has not yet taken place, make sure the opening date is set to after the event's date. The countdown period determines the period of time an answer can be posted after an answer. Each answer resets the the countdown period. The final unchallenged answer after the countdown period expires is the winner.
Anyone can answer a question by posting a bond, and anyone can challenge that answer by posting a new answer, but doing so requires doubling the bond. Challenges can continue, as long as someone is willing to double the bond in the hopes of claiming the bond and the reward.
The result is settled automatically at the end of the countdown period. The final answer at that time is the winner and claims the bond and the reward, if any. (If the same winning answer is posted more than once, the system deducts the same amount as the bond posted by the earlier correct answers.)
Anyone who wants to challenge the final answer can request arbitration. The arbitrator can be any Ethereum contract and may be controlled by a company, a trusted group or individual, a DAO, or any other decision-making process you can code. The arbitrator contract will have a set fee that must be paid to settle the question, but if the winning total is high enough, it can be profitable to challenge an answer via arbitration.
For more details, please see the documentation