Every good essay needs a conclusion. Sum up your ideas and findings, comment on them and decide if your conclusions sum up what you intended to do.
Now it is time again to look at what you set out to do and what you have done. What was the purpose with your report? What did you set out to do? Have you done that? Have you found answers to your questions? What were the results of your investigations? Maybe you have stated the results in the previous chapter. It is now time to analyze the results and discuss the findings. You may also draw conclusions and make a summary.
However, you must remember that you cannot bring anything new into the conclusion. You can only discuss things already mentioned in the report.