Why is it so hard for many guitarists to read sheet music on the guitar?
Probably the answer is easy. They haven't done anything about it. An old used tyre can stand leaned against the wall of a car garage for thousands of years. Why? Nobody has thought about moving it. Could it be that easy also with playing guitar sheet music? I think so.
Sometimes we consider ourselves poor sight readers or not able to read guitar sheet music at all and we think this is part of our personality. Every person who wants to learn to read guitar sheet music notation properly has already taken the first step towards changing that condition, just like you have done by reading this article.
Climbing the "Reading Guitar Sheet Music" mountain starts with step one
Surprised? Well, I have been teaching guitar playing for many years and I have found that learning to play guitar is like many other activities. People, not you of course, often want to start from another position than from where they are.
I would like to suggest that we approach the sight reading assignment from two directions. First by learning to find our way around the guitar and learning the notes on the fingerboard and secondly by learning the corresponding notes in the sheet music you want to play.
Make a string safari on your guitar
With the conventional tuning on your guitar you will have the note E on the first open string. I guess you are aware of the fact that you can find the same note on the second string too. If you don't know on what fret you will find it you can listen your way through the frets on the second string until you'll find the note that sounds the same as the first string.
Now I will be frank and tell you that E on the second string is on the fifth fret. Maybe you have already found that out. E on the third string is on the ninth fret. Practice to play E on these different places and jump back and forth until you can find the frets without effort.
How to proceed learning the guitar fretboard
In a similar way you can invent small exercises on you guitar fretboard like playing all E's on all six strings until you can play them with ease or finding all C's and play them consecutively like a picking exercise or as an exercise for your right hand fingers.
Knowing the notes on the guitar fingerboard will be a great help for you, not only when playing guitar sheet music but also when you are playing by ear or improvising a guitar solo!