The first part of this post briefly described what to include in the introduction and materials and methods sections of a typical research paper written in the IMRaD format (Introduction, Materials and methods, Results, and Discussion). In this part, I'll discuss the results and discussion sections.
Writing the results section: The results section answers the question W-H-A-T.
State only the results; leave comments and explanations for the discussion section. Use tables and charts as appropriate, but do not duplicate the data by presenting the same data once as a table and once as a graph or by repeating the graphical data in the text. In theory, this section can be the shortest of the IMRaD sections because a lot of the information can be presented in tables and/or figures.
Writing the discussion section: The discussion section answers the most important question, namely, S-O W-H A-T.
Explain what the results mean and how they are important. Compare the results with earlier findings; explain contradictory results, if any. If some results did not attain statistical significance, explain that any differences seen may have been due to chance. Outline the limitations of your study, and suggest a future line of work. Finally, sum up with a conclusion.
And there you have your manuscript neatly structured in IMRAD format!