I am wondering whether there is a method for memorizing the fretboard that works best for other guitarists. Drills that are disconnected from the act of making music are less effective for me - I can spend 30 minutes on an app that quizzes me on frets/notes, then return to it the next day almost as though I never worked on it. Exercises, apps, or ideas are welcome.
In a sentence, mix it up and steer away from where you're comfortable.
Mix it up
To start with find some methods and exercises to work with. Some examples:
- Always say (or sing if possible) the notes as you're playing exercises like this or scales or whatever. Saying the note name or whatever you're learning helps connect your muscle memory, your mind (the abstract theory like note names or scale degrees), and your ear (the pitch) all at the same time. You could just think it, I guess, because the point of saying it is only to make sure you're thinking about it. But having to say it works better. And if you go a step further and sing, you'll train your ear a little more along the way.
- Flash cards or similar random quizzes. But don't settle for just tapping the note name on a screen. You should actually play the note. If you tried this and didn't work well, try something else. But don't give up, come back to it and try again.
- Play some simple melodies or licks and then move them to different positions. Challenge yourself to play it in as many place across the neck as you can.
- Play those same melodies or anything else like scales on a single string. The fingering might be weird and it might not be something you'll do much in actual music, but the point is that it goes against what muscle memory you had playing across all strings in a position. Suddenly you have to think about what the notes are which is the point.
- Try playing with one finger for the same reason.
- Or try playing on only certain strings and incorporate either position shifts or shifting the given note up or down an octave to compensate.
- Play through the cycle of 4ths or 5ths (both chromatically and diatonically) on each string or using 2 strings at a time—again, mix it up.
- Get out a fake book and play through the chord roots in the same way on a single string or a set of strings. And don't neglect the middle strings just because I said "chord roots". In fact, start there. This will come in handy later musically if you want to voice-lead through chord inversions.
- Get into scales, arpeggios, and chords including inversions if you haven't already. Again "say and play" and mix it up as many ways as you can. Play scales in intervals. Play arpeggios in different orders, starting from different notes, and in different inversions. Play chords in different inversions. Play the chord and then the associated arpeggio or scale to connect them mentally. Again, always say and play and think about the notes that you're playing.
- As r lo said in their answer, a method book may help but in a slightly different way. A method book should introduce the notes of each position gradually and connect them to the notation. If practiced well, instead of teaching you where each note is, it should eventually make the direct mental connection between what you see on the staff to where your finger goes. It's still worth doing but I'd consider it a separate task from learning the fretboard.
Those are just some ideas off of the top of my head. There is no best method other than what ends up working for you. Try a lot of them and make up your own even. But definitely mix it up because when it comes to knowing the fretboard you want to be flexible.
Make yourself uncomfortable
A general rule of practicing is that you want to focus on what you're not good at. That sounds obvious but a lot of people forget to use it to their advantage. So as you're playing whatever exercises be very aware of where you stumble or feel uncomfortable and let it guide you.
- For instance a lot of guitarists learn the 6th (and 1st) and 5th strings pretty well in the course of using barre chords with roots on those strings. But then they neglect the 2nd, 3rd, and 4th strings. So if you find that you're weak there then practice only on those strings for a while.
- Are you ok in lower positions but start to get uncomfortable higher up the neck? Then focus on those higher positions.
- Do you find yourself stumbling when descending back down a scale? Start your scales from the top or only play them descending until you fix it.
- Are you ok in C Major but start stumbling when there are a lot of sharps or flats? Some people get stuck on always relating sharps and flats to where they fit between the natural notes. If you find yourself doing that then try only playing in keys with a lot sharps or flats for a bit. Or better yet, try to practice in all keys but always start the keys that have a lot of sharps or flats or whatever you're stumbling on.
- Anything you can do to break muscle memory is generally a good thing for learning the notes because that means that you'll have to think about it. That's not to say muscle memory is bad altogether, but just in this case where you want to be thinking about what the note is and not just where your finger goes.
The point is that you should keep an eye out for anything that you stumble on or anything that makes you uncomfortable and turn it around to make an exercise out of it to isolate that problem.
I learned a trick from my first teacher that helps a lot with memorizing things. It has to do with how the brain processes things into the memory. The trick is: studies in memorizing and understanding are done within three hours before going to bed at night, and studies of manual dexterity(finger patterns, scales, song practice, etc. are done within 30 minutes before going to bed at night. This has helped me learn, comprehend, and retain much more than I was able to do before I tried it, and it can be applied to whichever guitar method you choose.
I used a very basic book on playing guitar. You will learn to read music and the notes on the neck. While it may be very easy to play the music technically, it makes you read the note and understand where it is on the fret and string. This way you will memorize the notes and read music at the same time.
The most effective learning is doing this the right way. To me, as former guitar teacher, this means start with classical methods like Emilio Pujol, F.Sor, M. Guliani and more. All those modern guitar methods are based on these anyway and most of them are very poorly written. Go back to the roots, I'd say, learn things the right way - how to hold the guitar, how to sit right, notes on the guitar fret, right and left hand fingering, etc... Once you learn the basics and do this the right way, this will stay with you for life and gives you an advantage. Then you will be able to play any guitar, not just classical.
There are some very good answers here from some very experienced teachers, but let me put in my two cents worth, even though it seems counter to the excellent advice above.
Don't memorize the entire fretboard. What? Just memorize the main notes. If you play a lot of blues, for example, you'll quickly know where E and A are. Then it only takes a half second to find G (two frets below A), for example. Once you're comfortable in basic keys/scales like E and A, then branch out, maybe to G, C, and F.
In other words, start with what is familiar, and take it in easily digestible chunks. But most importantly, if you always know where C is, you don't have to memorize where C# is!