[Pinbenterjamin]

You definitely should. I remember when I started doing serious side projects, how invaluable having a document was.

It should be living though. Start with something small, describe goals, and outlook. Put a feature checklist on it. As you work through early problems and refactors, treat it like a development blog. Include build notes.

You will probably put this down, and pick it up a few times on your journey. Make sure you leave plenty of breadcrumbs for yourself so that you can be productive each time you do.

And, should you decide to put it down for good, you'll have a nice little project history for lessons the next time you try it.