I have a simple project journal/log text file I add to at the end each time I work on the project. This allows me to easily get back to the context next time I decide to move the project further.

I usually keep a couple of ideas to do next, outlined at the end.

If I forget what I was doing previously or am stuck on ideas on what to do next, then I just skim back up the file.

This works for me, and it’s dead simple.