1- Always, always, ALWAYS start tapping you foot BEFORE you start playing. Sub-divide the beats, 1 and, 2 and, 3 and, 4 and (4/4). Guitarists, especially self-taught, TABbers tend to “feel” rhythms instead of counting. If you don’t know where the “One” is, in every bar and how many bars are in each section, you are guessing. Ask a friendly Drummer to explain it.
Eventually you will do all of this automatically. Practicing with a metronome my seem rigid and stifling but it is the best way to become consistent, and you can see when you are improving. You will be able to play pieces at increasingly faster tempos.
Playing fast, isn’t the point of music but I find being able to play faster, than required is a good way to practice scales and chord changes.
2- Visualize! Did you ever wonder why so many good musicians started out as artists? Being able to SEE music gives you an advantage. Less than .1% of the population has “Perfect Pitch”, so don’t depend on your ears, exclusively. Being able to see the difference between a Major and minor scale or triad, is the first step to hearing and controlling them. Reading standard notation, TABs or chord charts are not the only ways to visualize material. Everybody sees music differently, numbers, shapes, colors, letters.
3- Play Blind. Do the notes on your Guitar re arrange themselves when you look away? They will always be in the same place, whether you can see them, or not. The only time you should look down (at the top fret-markers, not the fingerboard) is to change positions.
If you can’t see the note’s in your head, there is no point to looking for them on the fingerboard. Watch a few different Guitarists and see what a difference it makes. If you are focused on the fingerboard, you are introverted. It looks as if the player is not confident.
4- Leave Space. I like to tell my students (during soloing) to stop playing when they are inhaling. This the easiest way to start leaving space during solos. Use the call and response, or question-answer technique and leave a space for the answer. Make your spaces sound deliberate. In the case of 2 players with equal technical abilities, the one that can leave deliberate rests, will sound more tasteful and confident. What you DON’T play is as important as what you DO play!
5- Don’t let your approach limit you. Don’t let words and technical terms limit you. “Lead” and “Rhythm” Guitar are terms that will effect your playing. They imply a very limited understanding of the instrument. Hybrid styles of music such as Rockabilly or Psychobilly would have never happened, if players were limiting themselves to being “Country” or “Jazz” players.
Also try to understand the Bassist and Drummer’s approach to Rhythm and Harmony. The rhythm section is not just there to accompany you and keep time. You will have to be able to communicate with them and know what they expect from you!
When you try to write riffs or progressions, with your Guitar, your abilities WILL limit you. Write in your head, then figure it out on the Guitar. Sing or hum a line, then learn it on the Guitar. This is the best way to learn how to improvise instead of copying.