There are some pretty basic skills you should pick up before you jump into guitar lessons for beginners. You can learn this stuff online easily and you shouldn’t waste your teacher’s time and money with them. First and foremost you need to know how to tune your guitar. With almost any tutorial online you can master this skill and have a beautiful sound guitar in no time. You’ll also want to learn how to change the strings on your guitar.
Before you start your guitar lessons for beginners you should learn the string names and figure out how to use the note circle. You should also learn how to read music and practice it. Unless you’re going to do all your guitar learning by ear it’s an important skill to have and lacking it will impede your progress in a significant way.