I have had many students, and parents of students, ask me how long it will take them to become a “good” guitar player. I give them the frustrating answer I have always given: it depends. It depends on how motivated the student is, and how much they are practicing and playing their guitar. You get out what you put in to guitar, just like everything in life. It isn’t enough just to want it bad enough, you have to take action to get there! This means practicing daily, on a detailed and planned out practice regimen. You could have the greatest teacher in the world, teaching you out of the best available method books, and still fall flat if you aren’t putting in the work.
Here is some practical advice for practicing:
Your goal at the beginning stage is just to not become so frustrated that you hate playing guitar. Let’s face it, guitar is a very difficult instrument to learn! Not just anyone can walk up to a guitar and make even a single note sound, let alone hold it correctly.
I recommend playing for extremely short amounts of time, maybe 15-20 minutes per day, broken into small 5 minute long sessions. Realistically you should try to play every single day, but getting into this habit is difficult, and can take a few months to work up to.
In the intermediate stage you should be up to be playing every single day. Open chord songs are now not as rewarding, so you are starting to branch much further out into the world of guitar.
I recommend playing at least 6 days a week, 30-45 minutes each day. Your practice should have a good mix of technique, like scales, chords, and exercises, as well as songs you enjoy playing, but are maybe a little out of your comfort zone ability wise.
By now you are dedicated to playing every single day, without fail. You are deep in the world of guitar, and beginning to be interested in playing even faster, and therefore cooler, licks and scales. By this stage you have a clear goal of what you want to do with your guitar playing, whether it is writing insane prog metal tunes, shredding jazz changes, or songwriting.
I recommend playing 1-3 hours per day, depending on your musical tastes and goals. Your practice should have a very well organized approach, you always know exactly what your daily, weekly, monthly, and lifelong goals are before you sit down each day to practice.
Well, there is my short take on practicing. This is mostly coming from how I personally progressed as a guitar player and musician. Hope this helps you see in to the future of your playing, as well as gives you some good food for though on your own practicing!