The close consideration of any great, apparently "free-form" piece of art will reveal that the maker remains in full control of their craft. Lightness and spontaneity usually come from having learned to use your tools so well that you don't need to stop and think about them.
Poetry is made of a tension between sense and sensibility. Poets often seem to be those who are scalded by the acuteness of their perceptions while retaining a piece of ice in the heart. Many people find themselves writing poetry for the first time when struggling to articulate some great joy, disturbance or loss. Such poetry can offer catharsis or clarification and this has been the momentum for many great pieces of work. But, without the application of craft, this remains a therapeutic exercise not a literary one. If this is your starting point you may find yourself unwilling to subject something so private and precious to the cold light of critical scrutiny. If it is your sole aim to get something out of your system, you won't need to.
In keeping with its image, poetry is evocative, allusive, startling and mysterious. This is achieved not only through imagination and originality but also rigour and ruthlessness. Every word should count - for its meaning as well as its music. Every image, however fantastical, should make complete sense within the context of the poem. If something you have written particularly impresses you, question it all the more.
Treat reality and the imagination with equal suspicion. Nothing earns its place in a poem simply because it is true. Your memoires will be cluttered with details invested with private significance. Poets do, of course, draw on their own mythologies, preoccupations, associations and symbols. Let them surface but be prepared to ditch them if they add nothing.
If you want your work to be read, you should concentrate on clarity not obscurity. Being clear does not preclude being subtle or complex. The simplest narrative poem contains well-placed signposts and clues that will lead the reader further in. Always have an eye on what the reader needs to be shown and how they can get there.
Having issued all these warnings, where to start? Where do I start? Usually at some crowded or pressured moment, when a notion enters my head. It is as if when I have to think quickly and hard, the part of my mind to do with writing moves into gear as well. I am hit by a physical sensation of openness, concentration, capacity. This impetus does not last long and even when I am able to sit down and start work right away, the poem that was so palpable can fall apart in my hands. Some poems sit around for years and then all of a sudden complete themselves. Others are made and remade in sporadic bursts over several weeks or months. Between times, I shape and worry at them in my head. Occasionally, a poem forms itself entirely, straight away. There are also those that, whatever their promise, are never going to be realised. All poets will describe the process differently. The point is to accept and exploit the way it works for you.
I do not write on a computer as I like to see what I have crossed out. A computer offers the seductive image of printed text. You may forget that what you have on your screen is a rough draft. The ease with which you can move, delete and revise your words can be deceptive and disorientating. Try to stick for as long as possible with paper and pen.
If you don't know what to write, ask yourself why you want to write at all. Consider what compels you, what catches your eye or keeps you awake at night. While finding your voice you should also try writing against yourself - if your work is all abstract statement, make yourself write something that is expressed entirely through concrete images; if you use a lot of adjectives, write with none at all; if you are a narrative poet, try writing something impressionistic; if you want to write epics, have a go at haiku. Question whatever comes effortlessly.
You won't learn about poetry without reading at least as much as you write. One of the delights of reading other poets is finding unlikely affinities. Read poetry from other countries and cultures, from hundreds or thousands of years ago. When you find something that interests you, explore it thoroughly. Poems can reveal themselves in astonishing ways under the scrutiny of close questioning. There will be people you will want to read over and over again. For me, these include some whose preoccupations I share, technical models I aspire to, and others whose style, subject or voice are poles apart from my own.
Reading will also help you understand and experiment with form. Look at how the shapes, sounds and patterns of language provide tension, resonance and muscularity. Consider the point of line and stanza breaks, see how each of these must work within the whole and also stand alone. Go to readings and listen hard. Read both your own and others' work aloud. Think about ways in which rhyme and meter fortify a poem and ways in which they kill it stone dead. Familiarise yourself with traditional forms - the sonnet, the sestina, the villanelle - and have fun trying to write them but don't expect to produce anything other than an exercise.
Thanks to their school days, most people can parody the poetic. This moody and melodramatic stereotype can be surprisingly hard to shake off. Your images and adjectives should be your own, not borrowed from some collective repository of poetic metaphor. If you use an adjective, it should earn its place. On the other hand (poetry is this kind of continual balancing act), striving for novelty could lead you to use images and ideas that are nothing beyond flashy or absurd. A poem can lead anywhere but once it is done, you should be clear about the point of it and expect more from it than an amusing or eyecatching anecdote.
A good workshop will provide you with an objective critical forum as well as friendly support. Just after my daughter was born, I found myself sleepless and penniless but provoked by this huge shifting around of my world to take the writing I had always done seriously. I spent my last maternity benefit cheque on a workshop course run by the Poetry Society and taught by Fred d'Aguiar. It changed everything. I remember taking a poem to show the group, photocopying it and then, hit by some realisation, throwing it in the bin. The poems I wrote after that were in a voice that was utterly new to me but felt entirely mine.
A workshop is not a place to show off finished work. The poems you take along should be more than a first draft and less than fixed. Listen to the advice and opinions you are offered but try also to develop your own judgment of your work. The first time you show a poem to a stranger may be terrifying. Be sure that it is not just flattery or reassurance that you are after. When the workshop no longer offers anything new, move on.
The traditional route to getting your work into print is to submit first to magazines before attempting to interest a publisher in a full collection. Before doing either, try to get some advice as to whether or not your work is ready for this. It is hard to be patient and realistic but you could save yourself a lot of rejection if you concentrate first on writing the poems and not on them appearing in print. Whether you send to a journal or a publishing house, get familiar with it, think hard about whether or not it is a place where your poetry might fit. Take note of editorial policy, be prepared for a long wait and do not expect editors to have the time to offer a critical response. Other routes to publication are competitions, many of which attract thousands of entries, and - if you are not concerned primarily with the judgment of the literary world - printing your work yourself.
"More than usual emotion, more than usual discipline," Coleridge said. The aim is to be both receptive and productive. I have concentrated on discipline because emotion seems big and strong enough to stand up for itself. Don't tip the balance the other way by becoming technically proficient but unwilling to risk exposing your feelings. Whatever you write should come out of a profound engagement with your subject. If all you can manage is a shrug, don't bother as your readers will shrug too.
Lavinia Greenlaw's collection Night Photograph is published by Faber. Next term she will be writer in residence at Wellington College for Boys.
Details of workshops, festivals, competitions and readings are available from the Literature Officer of your regional arts board or from main libraries. If you live in or near London go to the Poetry Library at the South Bank Centre which is open seven days a week and is free. As well as a vast collection of 20th-century poetry, it offers information, audio-visual resources and carries a wide selection of magazines, tel 0171 921 0943.
The Poetry Society is a national advice and information organisation, tel 0171 240 4810.