You may also indicate the goal of the study and the problems that the study attempts to address. If more than one notebook is used for an invention, they should be serially numbered. Notebook entries should be made contemporaneously with your ideas and experiments. It is important to include your ideas and not just data in the notebook. Remember that the notebook is to serve for corroboration of the conception of the invention.
Conception is an idea.
If only experimental data is entered and ideas are not, it may not be clear until a much later entry why the data was generated and what it was intended to show. Therefore, the date of conception that can be determined from the notebooks will be later. Ideas concerning what the invention is, what problems it addresses, and how it differs from what was done before should be entered in the laboratory notebook. Comments should be objective and accurate, and derogatory comments about the work of others should be avoided. Make regular contemporaneous entries of experiments that are performed.