Lab notebooks, whether in print or electronic form, are a critical component of tracking and recording research. Consistent documentation of your research methods, calculations, and results is important not only for your personal use, but will help when you publish or otherwise share research, and when others want to reproduce what you have done.
Listed below are links to several guidelines. Please let us know if there are other guidelines that are used in your lab, institute, or department.
How to Start -- and Keep -- a Laboratory Notebook: Policy and Practical Guidelines (ipHandbook of Best Practices)
Maintaining a Laboratory Notebook (from the excellent Colin Purrington; see his other tips, too)
(adapted from: University of Oregon)