Posters can be created with as many or as few descriptive sections as you wish. Generally speaking, you should go light on the number of headings/sections. Keep the KISS principle (Keep it Simple, Stupid) in mind.

For your first attempt, you may wish to include a short title, an introduction to your question, an overview of your experimental approach, your results, some insightful discussion of aforementioned results, a listing of previously published articles that are important to your research, and some brief acknowledgement of the assistance and financial support from others.