It is an essential working priority to document everything that happens in a session from good takes to bad takes, mic placements, hardware settings, and more. In the Software Age, it may seem less critical to do this, since so much information is saved in a DAW file. However it is still good practice to document as much as possible.
Fortunately, most DAW software has a “comments” area. The comments section is a great place to make notes about anything you might otherwise forget about the session or a track. Anything can be jotted down here — notes about automation moves that will need to be done, notes about EQ issues that need addressed, and even what mics were used and how they were placed. Anything you think might be helpful to you (or other engineers) at a later time can be jotted down in the comments section. Think of the comments section as a virtual track sheet.