Write the title of your lab report and center it on the first page of your report. The title should clearly indicate the subject of your experiment.
Type the heading "Introduction." Describe any scientific theories or principles that are relevant to your experiment. Explain your hypothesis---the outcome that you predicted for the experiment based on your knowledge of these theories or principles. List any equations or mathematical formulas used for the experiment. The introduction should be no longer than a half-page to three-quarters of a page.
Type the heading "Procedure." Write a step-by-step explanation of your experimental procedures: incubation times and exact amounts of reagents, for example. One of the primary reasons for completing a lab report is so that other researchers can attempt to duplicate your results. If they succeed, your hypothesis or discoveries are further supported, so it's important to craft a coherent procedure section that allows readers to recreate your experiment.
Type the heading "Data." Present the numerical data you obtained during your experiment in a table format. Clearly label the tables according to their content.
Type the heading "Results." Present and summarize the results of your experiment in this section. Include your calculations in this section. Include any graphs in this section as well. Graphs should each take up their own full page. Clearly label the axes of the graphs and remember to use units of measurement.
Type the heading "Discussion." Write a detailed account of what occurred during your experiment. Provide your explanation of what you think happened and why you think it happened, backing up your ideas with scientific principles. Refer to your tables and graphs. If your experiment did not produce the expected results, consider what may have gone wrong during your procedure. Suggest possible future amendments to your procedure. This should be the longest section of your lab report, but try not to exceed two pages.
Type the heading "Conclusion." This is just a brief, concise summary of the entire experiment and the results. You can also discuss how you expect future, similar experiments to further shed light on the theories mentioned in your introduction.
Go back to the very beginning of your lab report. This is the part that gets a little tricky. Above the "Introduction" heading, type the heading "Abstract." Concisely summarize each section of your lab report, from introduction to conclusion. The purpose of the abstract in a lab report is to let researchers know what your report is about and what kind of results it produced so they can decide whether or not it provides the information they are looking for. Even though it's the first section of the report, it should be written last---you can't summarize what you haven't written yet. The abstract should be about a paragraph long.
List your references on the last page of your lab report. Cite all articles, reports or other materials that you referenced for your experiment.