Maybe you're in need of a prayer! Ha! But it's simpler than you think. You already know much of what you need to know to get started. I'll prove it. Sing the alphabet song you learned as kid, but just the first phrase. Go ahead. Do it now. If you stopped at 'G', you got it! A, B, C, D, E, F, G. That's the music alphabet. Now, count to thirteen. Easy, right? Seven alphabets, thirteen numbers. Of course, that's the easy part. I said earlier that you already know much of what you need to know. And that's true.
The other pieces of the puzzle you already know about, but might need to...no, definitely need to make them habitual. This might be a bit more challenging. Three things: Desire. Discipline. Commitment. You must want (Desire) to do it badly enough to make time on a regular basis (daily is better, thus Discipline), in order to stick to the process (Commitment) until you achieve the desired results, the goals you've set for yourself.
You need an idea of what you want to be able to play. But these three things is where the rubber meets the road. Here's what I mean.
Let's say you find a teacher you like working with. Cool. Your arrangement could be one lesson per week for 30 to 60 minutes (my article "The Cost and Price of Music Lessons" goes into a bit more detail about a typical music lesson scenario). There's only so much that can happen in 30 minutes, and it's usually not very much because of such a short period of time. It also depends on what you do those other six days, you know, Desire, Discipline and Commitment. If you've set the bar unrealistically high, it will take more DDC.
I like to think of us teachers more as coaches. The lesson session is for answering questions, solving fingering, reading, rhythm issues, etc. There are students who unfortunately use the session to practice last weeks' assignment. And parents wonder why there's little or no progress. The other six days are for working on the assignments, writing down questions and issues that need to addressed at the next meeting, assessment, encouragement, assigning additional material, those kinds of things.
The truth of the matter is: you actually teach yourself. For it is in the doing that the learning takes place. The more you actually do, the faster you'll learn. An often asked question is, 'how long will it take?" My answer is, "how long do you want it to take?" Desire. Discipline. Commitment. Be diligent and just stick to the script.
You will cross a threshold of understanding in your own time, whenever that is. That's when the ah-ha moment happens. It will be different for you than someone else. The more DDC you apply, so will that moment come when you least expect it.
I'm no scientist, but a whole slew of things are being developed during this process. There's muscle memory, hand-eye coordination, visuals, physical, aural, mental, spiritual, psychological, and physiological development and synchronicity going on simultaneously at varying levels. So you must enjoy or learn to enjoy the process. If you don't enjoy it, then learn to be patient while being diligent until you reached the point of enjoying the process. The truth is, it ain't really fun until you know how play a song, how to make music.
The knowledge is the easy part. The doing is more challenging as you well now see, but it's where the learning happens. There are no shortcuts, except to spent more time in and on the process. A teacher can only coach and direct you through it.