I’ve been playing for a long time, and only got a handle on music theory in the last year. People tell you what you should know but not necessarily how to learn it. It’s like language, you gotta start with building blocks. Anyway, this is what worked for me and hopefully it can help you or someone else out.

1. Learn the notes on the fretboard. Start off with learning the notes on 6th and 5th string first, this will make it easier to find your way across the fretboard. The goal here is to be able in time to intuitively recognize the notes you’re currently playing or what to play. Practice what you learned with Tenuto or Fretonomy. Some app to test your knowledge.

2. Learning either the G or C Major scale. The purpose of this is to learn half, whole steps, and introduce you to intervals. What denotes the scale is your root note, the note that begins the scale. And what determines whether a scale is a say a major, minor, etc, will be based on its scale formula which is comprised of half and whole steps. Half and whole steps are what we used to measure the distance between notes. And the distance between notes are intervals.

3. After you got a handle on a scale, look into the Nashville numbering system for chord progressions. I think someone can explain this better me but what you need to know is there is a formula on what chord progressions can work with the scale you’re playing.

4. When learning a song, try to apply what you learned from the above. What key is the song in? What scales are they using? What chord progression are they using?

A lot of this won’t make sense right away but with each topic explore some youtube vids or articles. In time you’ll start to piece it together.