![]()
1 - Keep it Simple - People like Palestrina, Byrd, even Rutter, are praised not for their complex musical structures, but the elegance in their composition. Creativity flourishes under restraints. Put things in an easy rhythm, at least until you're confident enough to make something a bit more interesting. Edmund Rubbra loads his music with dissonance and tonal changes, but there is still a core musical elegance to his music. You cannot say that because your composition is complex, that it is therefore a good composition, you can only say that if the complex composition evokes emotion, or creates meaning.
2 - Write it out on paper - If you write out your music in a notation program such as Sibelius, composition becomes almost a trial-and-error process. Instead, write it out on paper, and play it through in your head. If you have knowledge of musical theory and a good mental tonality, this shouldn't be too hard - if not, play it on an instrument (see point 3). If you do this, you can at least know how it is supposed to sound, and correct any errors after then putting it into a computer.
3 - Test your composition - If you're writing music for a genuine performance (not a synthesised one), then you need to make sure that your music is actually easy/possible to sing/play by the people performing it. For writing choral pieces, as an example, ensure that you remain within the ranges of the parts you write for. For a clarinet, ensure you use a b flat base and so on.
4 - Chords/Progressions - If you are thinking of music in terms of chords and progressions more than seperate melodies (i.e you are writing modern music), then ensure that each element of the chord does have some melodic nature to it. The chords need to progress with the melody. A simple melody may be harmonious with 1 or perhaps 2 chords. Just because this is the case, doesn't mean that THEY are the only two chords you should use. Diversify so that each part has it's own semi-independent melody that unifies to provide a good accompaniment to the main melody. This is where a figured bass comes from, and ties in with the arpeggio strategy - that an arpeggio should derive from a bass melody.
5 - Keep writing new stuff - Do not assume that you can break all the rules for a "rough" composition and then come back to it, modifying it, changing it, so that it all works more nicely and better. This tends not to work too well, you end up making too many ad-hoc changes to your composition and it becomes haphazard. Instead, take your time, and work lovingly on every part of the composition. Once you're done, if you make some errors or something doesn't come out as expected - learn from the mistakes, and then write a whole new piece - don't try and adapt an old piece (unless it's just a little change or correction).
This is just from my perspective, if you don't agree with me, well, you're welcome to.