Deciphering and Reading Sheet Music
Deciphering and reading sheet music allows you to play music that was written down by someone else. Being able to pick up a complex sheet of music and sight read it on the guitar at speed, requires great skill. Not only is it difficult to decide where on the guitar to play the individual notes, as you are well aware of by now, but it is also difficult to sight read complex music more than one beat ahead in time. We have seen many great readers of music but in all but the simplest cases, the very first reading of music, no matter how good, is different than a finished, prepared, final fingered piece. The guitar is so expressive that after first reading, there may be passages that you may decide that you would like to accent a different way, articulate differently, or play in a different position for effect. The first reading requires skill, the finishing touches require forward planning and great craftsmanship.
When you first get a new piece of music, if it is too difficult for you to read through at speed, you play it in a manner known as step time. This means that you ignore the tempo and rhythm of the piece and merely work out the frets that you are going to use one hand position at a time. It also means that you calculate your preparations, i.e., the places where your unused fingers of both hands must be to play or dampen notes.
Preparation is the act of positioning your unused fingers on either hand so that they are immediately in position to play or dampen open strings when required.
If you know how to type on a typewriter or computer keyboard then you can comprehend preparation with the following analogy. Imagine how much quicker and more accurately (with fewer mistakes) you could type the word "the" if you place your two index fingers over the "t" and "h" and your left middle finger over the letter "e". When the time has come, all that these three fingers have to do is to come straight down, in time order. If the fingers of your hands are in standard position over "asdf", "jkl;", then all three of the fingers have to move to a different location when it is time to play. This latter method is slower and you're not certain to land squarely on the "e" if you've just moved a finger on the same hand (to get to the "t").
This is essence of preparation, and great guitarists keep their unused fingers on either hand close to the frets or strings that they are about to play or dampen. As a beginner, it is hard to conceive of the possibility of someone being able to do this, but with practice it becomes second nature, you expect to have to do this with each new piece that you learn.
After you have figured out the preparations for a piece, you have to play through it with correct rhythm, albeit at a slow enough tempo to correctly play the piece. It is important not to play a piece too fast, since you don't want to get into a extremely bad habit whereby playing with mistakes is accepted. Instead, you must take responsibility for each note. All of the notes are equally important. At this point, you can play the piece at a basic level. Few guitarists can actually read complex music to this level on first sight, with correct preparations, rhythm and tempo, although many guitarists can read single melody lines to this level. By increasing the rhythm little by little after you can play through perfectly, you finally get to the tempo that the piece can be played at. If you really want to master a piece, learn it by random measure, decide to play a piece starting at any random measure. It is very difficult to forget a piece that you have worked on in this manner. Although it sounds ridiculous, you absolutely have to remember the starting note or chord and hand positions of a piece. Not remembering how a song starts that you supposedly know how to play has happened to many a guitarist before.
The next step is to phrase the piece, you use many different methods to do this. One such method involves playing the bass notes legato (dampening the ringing open string bass notes when their rhythmic life is over instead of just letting them ring). Another way to phrase the piece involves changing the volume, or dynamics of the pieces as it is played, in addition, you can change the timbre of the notes as you move further away from the tonic key. With guitar, you have many means at your disposal to make the piece sound differently.
After you have played a piece correctly, at tempo, with proper preparations, and good phrasing, relaxed and in control, you are ready to stop worrying about what frets to play at and your preparations, and start thinking the line. This involves absorbing the piece and thinking only about the melodies as they are about to be played, at this point, your fingers absolutely know where they are going to go, you just have to accent the melodies in whatever manner you've previously thought out. Sometimes, you float back and forth between thinking about the line and some upcoming frets, but you know the frets well enough where you can really concentrate on the crafting the melody.
At this point, if you have the means, it is very beneficial to record yourself. By carefully listening to what you are doing and attempting to play the piece perfectly for the recorder, you will become a better player. Knowing if you are really playing a piece of music as the composer originally intended is another matter. This really depends on the period in which the piece was written and the composer's non written implied ideals. The best way to do this is to get a teacher. The second best way is to listen very carefully to a CD of a good guitarist and mimic the sound as best you can. When you look at the sheet music versus how multiple different players on CD play the piece, you will truly understand that a given piece of sheet music can be interpreted in many very different ways.
A word about improvisation is in order. Once you master the fretboard, and know enough of the patterns of scales and chords, you are ready to start improvising over them. It is really fun to play only notes on the guitar in a certain scale or group of chords, since you know it will sound acceptable. Flamenco guitarists are said to improvise, but what we really do when we play Flamenco is throw in falsetas one after the other in order to fit into the fairly complicated rhythmic structure that each type of Flamenco rhythm family requires. Falsetas are merely a melodic "riff" that is of the correct length that we can decide to play as a unit whenever we want. These falsetas are handed down from teacher to student literally by memorizing the falseta in front of your teacher, note by note, finger by finger. The technique of Flamenco is really fun to learn, although if you're a classical guitarists, the sound of the breaking notes can initially sound harsh.