The Chairs are responsible for keeping the debate flowing, while ensuring that all rules are being complied with by the delegates. Chairs do not represent any member of the UN.
In order to chair a committee successfully, a student should be aware of the Rules of Procedure.
The Chair needs to acquire general knowledge of the topics to be debated in that committee. It is important to know which countries represented in the committee play a major role in each topic and who are allies and enemies.