Much like an abstract, an academic poster is a summary of your research project, with the very important difference that the poster should be visually engaging as well as academically sound. Descriptive text must be brief—this is the opportunity to highlight your methods and results (in the form of graphs, charts, etc.) as well as give the context of your research (through photographs, maps, etc.).
You should prepare a two-minute presentation of your poster that you will be able to deliver to anyone viewing your poster at the symposium. Even though you will be standing with your poster to discuss your research with viewers, the poster should be able to stand on its own with a clear, logical presentation of your research.