In scientific research, the lab notebook is often considered a legal document, such as for the purposes of patents or to meet FDA guidelines for drug research. Therefore it is important to start good habits that will make your notebook as efficient and accurate as possible. Some more common tips include:
Use permanent ink
Initial and date every page
Leave a blank page or two at the beginning of your notebook so you can create a Table of Contents
Draw only a single line through all errors written, so they still can be seen
Create a table of important chemicals and their relevant properties at the beginning of each experiment
Record what you have done, not what your lab manual says
Record all observations and explanations of why they happened
Be as descriptive as possible with titles and headings for your experiments; for example do not write "Chemical Synthesis," instead write "Preparation of Alum"
Cross out all blank space at the bottom of the last page of each experiment; start a new page for each experiment
At the end of each lab, ask yourself, "Can I recreate this experiment/my results with what I have written down?"