Another tip, more general to the hobby than specifically fert dosing, is try to resist the urge to chase parameters. The vast majority of plants and animals in our tanks are pretty hardy and can thrive in a fairly broad range of numbers. What they don't deal so well with is change. You are going to find a ridiculous amount of conflicting information over just about everything other than stability being the most important aspect. That, most everyone agrees on.
So with that out of the way, I agree that there is an overload of information out there, bit and pieces all over the place, and finding a concise Step 1, Step 2, Step 3 guide is tough to find. The reason is that every tank is different, and there is not going to be a specific step by step that works for all of them. What works perfectly for one might be a complete train wreck for another, that on the surface, appears to be nearly identical.
The closest I can personally come to a beginners guide for nutrients without all the greek, would be buy some Thrive, dose as directed, tailor as necessary.