Do not set out to write a poem. Strip yourself of all the education you think will make you a good writer, and undress all the fluff you believe constitutes a good poem. Write only what is in your heart at this exact moment—every thread of thought and every emotion you have not the courage to feel out loud. Write this. That thing you are afraid to say. Write that. Approach the page vulnerable. Come open. Come raw. Come wounded or come healed, but come bared of what you think poetry is and become the poem instead. Write accurately and precisely every sentiment you have bottled up inside. In writing what is in the most sacred part of your being, and the most intense sections of your soul, you may unintentionally stumble on something beautifully authentic.
You may even call it a poem.