Learn your note names on the guitar.
Learn your scales, and then learn why they're scales. Learn the patterns for major and minor, learn your note names even more.
Learn how to construct chords, and learn how to name them fully and properly.
Work on modality until you understand the concept.
Learn what chords fit where, and likewise, which chords don't fit where.
Learn how to take a chord that doesn't fit, and use it to express yourself.
Learn all the rules, then proceed to break them in structured way.
That's my advice.