I had several revelations as I learned to write music for classical guitar, and if I share them now with anyone who wants to go down that route, they might save you time and struggle. My pearls of ineffable wisdom won't apply to everyone: I am only writing from my own experience.
First - forget the image of the inspired composer dashing off a concerto in the morning and a rhapsody in the afternoon. It's mostly slow, painstaking, repetitive work involving a lot of trial and error. To me, completing a piece feels very much like solving an intractable puzzle or slowly chipping away at a piece of stone to make a sculpture.
I usually start off with a general idea of what 'type' of music I am trying to write - a feel, a style, a mood. But I don't often have the melody singing in my head. A striking melody can emerge from trying dozens of options, repeating and repeating, listening and selecting, picking out what I've come to think of as the 'line of rightness' and discarding the irrelevant or unfitting. Equally, a melody can emerge from stitching several short sections together and then using a process I think of as 'sanding and polishing' so that you don't notice the joins.
You will often find that the piece you are writing takes on a life of its own and something starts to emerge that you hadn't conceptualised at the beginning. I've learned to just go with it - it may sound pretentious, but I feel that by leaving yourself open and receptive, the music will channel itself. It will have a geometry of its own that reveals itself over time.
In this piece, for example, the first section of eight bars or so of the initial dark sombre melody was something I was messing round with for a couple of weeks. Eventually I started the process of trying to mould it into a cogent piece of music. But the melody didn't want to end too quickly, and kept extending itself, until it became a single melodic line that doesn't repeat, and extends for two minutes or so. As it reached its natural end, it suggested an entirely different melody; so I embarked on that and over a period, it took on a life and identity of its own, softer and gentler. Again, it didn't want to end: it was clearly leading to something new. So a sonorous, grandiose theme, still dark and sombre, emerged. But at the end of that theme, the piece as a whole still felt unresolved and tense, and so something had to happen to bring it to its resolution and I had no idea what. As is often the case, my fingers told me what to do. A baroque counterpoint was the final element to appear, with an ascent to the stars to finish it off. The process took many weeks, and the thing is so hard to play that I couldn't do it anything like justice in my recording.
In my case, even a short piece can take weeks of work. Sometimes longer, because occasionally I will get stuck and put it away for a while, to take up later with fresh eyes and ears. On the rare occasions when a piece has come to me quickly and fully-formed, it feels almost as if it can't be true: I usually suspect I've written down something I heard elsewhere. This piece is an example - an immediate emotional response to something that had happened that day, written and recorded in the space of a single night.
Above all, in the act of composing, patience and application are the key for me. Guitar is a tricky instrument to compose for, because fitting all the components together is a challenge. Your melody has gone up into the high registers of the treble strings, but you need a bass that fits consistently into your line or sequence - but you can't reach it physically on the fretboard, so maybe you have to raise it an octave, and perhaps that sounds disjointed so you have to adjust what has gone before so that it leads seamlessly to that point. It's a continuous moving three-dimensional puzzle and you just have to keep trying the possible solutions till you get something that works. Little by little you learn all sorts of techniques that help you out of an impasse, for example inverting melody and harmony, using chord inversions in the bass, doubling the melody where you need to, and so on. The thing that has most developed in my own case is voice leading in the harmony. You will find with practice that the structure of chords and melody is an elastic medium that you can push, pull and stretch to support the melodic and harmonic movement of a piece. Here's an example.
Most people who write music will tell you not to throw any half-finished fragments away: they can often be revived, re-purposed or transformed, sometimes being absorbed into something else. Find a way of collecting ideas - video them on your phone, write them in a notebook, etc. I don't make a great deal of use of this myself but I've adopted it as a discipline just to ensure I am always thinking about writing music.
Sometimes it's just some little trick that I happen on when playing, that gets stuck in my head. I've learned to simply let my fingers play around on the fretboard, and recognise when something presents itself that could be the basis of a new piece. When that happens, I worry away at it, try and add something new to it each time, and challenge myself to solve the technical puzzles it presents to me. This piece emerged entirely in this way.
Sometimes I stumble on a short phrase that raises the hairs on the back of my neck and makes me want to explore its possibilities, like this one.
Scale or 'size' - great composers can conceptualise massive works, but I'd suggest anyone who wants to try out their composing skills on guitar should start smaller. I'm still influenced by the pop music of my youth, so normally I end up writing things that last around three or four minutes.
Keep working - there's a cliche that says "a writer writes" and the same is true of composing. The more you write the more you learn about how to write. So how do you go about it if you don't have a musical idea that is inspiring you at the time? My solution to this has been a) don't worry about it, the next idea will come along one day; and b) while you're waiting, do something as a technical exercise. Set some parameters and try to write a piece within those constraints. Here is one example - the write-up explains what the challenge to myself was. Here's another, a study written to address a particular technique. (Incidentally you can download sheet music for this piece free from the homepage of this website).
Beginnings and endings - so important for a piece. I always work disproportionately on the start and ending, finessing and finessing until they are the best I can make them. A congruous ending feels such a lovely thing to write. My own favourite of all my endings is this piece but it's so difficult I never did manage to play it properly - so until a better guitarist comes along and plays it, it will remain unheard in its full glory.
Notation - I always finish the whole piece before writing down a note, but I know that's not the case for most people. Several composers I've spoken to like to write with pencil and manuscript paper, but I prefer to use notation software. There are lots of great packages out there, but I find the freeware package MuseScore does me just fine. It took me ages to learn but it gets easier with practice.
Here endeth....I hope someone will find something useful. Certainly for me the completion of a composition of my own is the most incredibly satisfying thing.
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