You have to learn a few things, which you do along the way, but basically, poetry is a matter of the ear. Iambic pentameters or what constitutes a stanza comes naturally – your ears will know.
VIKRAM SETH
Quietly they moved down the calm and sacred river that had come down to earth so that its waters might flow over the ashes of those long dead, and that would continue to flow long after the human race had, through hatred and knowledge, burned itself out.
