See the screenshot below for some of the sections for specific recommendations that you can add which will provide the meat of the document. Keep in mind this is a very flexible document – add recommendations that make sense (for example you may not always have specific design considerations for a project). Remember, it will be different every time you do it.
Lastly, it's important to remember that paralysis by over-thinking is a real issue some struggle with. There's no pill for it (yet). Predicting perfection is a fool's errand. Get as close as you can within a reasonable timeframe, and prepare for future iteration. If you're traveling through your plan and determine a soft spot at any time, simply pivot. It's many hours of upfront work to get your strategy built, but it's not too hard to tweak as you go.