The discussion should be a summary of the principal results. Think about the major patterns you find in the observations. Look for relationships, generalizations as well as trends among the results as well as their exceptions. Talk about the most likely causes which are found underlying the patterns resulting in the predictions. There are a host of other questions you should deal with such as does it agree or perhaps contradict previous work? Talk about implications and possibilities.
Remember to add evidence or even a line of reasoning which supports each interpretation. It might be helpful to break up this particular section into different logical segments with the help of subheadings.