This is a powerful technique that has helped me a lot in the past as well, especially for those projects where I rarely progressed on (mostly private stuff, the work topics are more streamlined).

Nowdays in my private projects I often use a combination of the git commit messages and comments left in the code to indicate where to continue. Of course, this is not useful for work, either.

For work I like to use the ticket system and a separate text file and a paper notebook each to a slightly different effect.

The text file is the log what was done and is done per day grouped by ticket, typically ~10 lines for a day. The notebook contains meeting notes, design thoughts, general notes etc. and is very verbose (often six or mor pages per day, A4 paper) but sometimes helps to identify how/why/when a given decision was taken. The ticket contains what might also benefit others such as technical insights, meeting summaries (derived and summarized after the meeting from the paper notebook), summaries of important (design or product) decisions etc.