One of the most important components of Model UN is writing a position paper. While specific requirements vary by conference, the basic premise remains the same--a paper that outlines your assigned country's view (or position) on a given topic(s), with a special emphasis on possible solutions.
Typically, position papers are one page per topic, single spaced. The first paragraph usually summarizes the problem, utilizing specific statistics and.... The second paragraph tends to highlight past actions taken either by the UN or your own country in trying to address this problem. The final paragraph or two focuses on possible solutions that your country is willing to consider or support. This should be the most detailed and complete portion of your paper.
Here are a few links to help explain more about position papers:
Best Delegate: A Formula for the Perfect Position Paper--A Solution Oriented Approach
Best Delegate: Preparing Proficient Position Papers
UNA-USA Page on Position Papers
MUNUC Guide to Position Papers
MKCMUN Position Paper Criteria & Examples
MKCMUN How to Write a Position Paper
NAIMUN Guide to Writing a Position Paper
Sample Position Papers:
MUNUC Sample Paper
UNA-USA Sample Position Paper
Sample Position Paper: Greece Legal
Sample Position Paper: UK EcoFin