Skim through a ~100 page booklet called MCDP 5: Planning, published by the US Marine Corps as official training documentation. Once you are done reading, swear to yourself that you will not go on a reading binge and look up other books on planning or time management. The link (PDF) is at: https://www.marines.mil/Portals/1/Publications/MCDP%205%20Pl...

I've felt your pain in the past, and the principles from this booklet have helped me a great deal. For example, I got a team far more productive and happier with minimal overhead in terms of planning software (we mostly just used a few Google Sheets for task tracking), than other teams that I've been on (that relied a lot on various project management software—while there is a time and place for these tools, I felt that their usage added unnecessary complexity).

For a summary of some principles that helped:

* A key quote is at the start of Chapter 2, though it's a bit trite now: "[A] good plan violently executed now is better than a perfect plan next week."

* In more practical terms, you should always have a strong bias to keeping your planning simple and flexible, instead of adding complexity through software.

* To do this, you need a clearly defined goal with clearly defined objectives. You should also include a clear "why" behind your decisions, to orient yourself when you face confusion.

You can immediately apply these principles to your personal situation. Your goal right now is simple: spend less time using project management software, and get right to work. What would be a simple way for you to do this? (This may involve simply committing to not using any software whatsoever, and sticking to a .txt or .markdown file or even just a pen and paper. I've read from your post that you really are most productive with paper or an .md file, so you know what to do.)

Outside of planning, you also mentioned documentation. I'll resist giving a recommendation of a method as it sounds like that is not what you need. Instead, I recommend keeping it simple and sticking to a OneNote notebook (or its equivalent in Obsidian because you already know markdown; but if this is new to you, no need to bother with learning at all at this point in time), and having your past notes easily searchable (this is exactly how I've kept track of favoured hex colour codes and image aspect ratios in the past).

Lastly, for evaluating what notes to archive versus throw away, there are a couple of approaches. A more complex approach is to create a list of temporary or "fleeting" notes and then manually sort them regularly into notes to make permanent, or notes to throw away. But a simpler approach that also works great is to lean on keeping most of your documentation notes for a project in a folder (or virtual notebook) for that project, and relying on search to find the information as needed.

To summarize: have a strong bias for simplicity, with a clear understanding of "why" you are doing particular tasks. (For nuance, I acknowledge that sometimes, long, detailed plans have been very effective in certain contexts, such as in 20th-century history and likely in present-day aviation—but I've personally found my planning to be best in most contexts, by starting plans as simple as possible, and only adding complexity as absolutely necessary.)