Be asured I'm not talking about concrete poetry. If you want to format your poem about an infant in the shape of a baby's stroller, that's one thing. That just assumes the ignorance of the reader("See, this is what I'm talking about.") and makes no difference to the hearer. What I'm talking about is the basis of good poetry, its rhythm and its sound.Rhythm and sound come down to two pertinent and important poetic tools: meter and rhyme. The simplest and purest form of this is the heroic couplet, two lines of iambic pentameter that rhyme perfectly. It's the first thing a budding writer of rhyme tries for. It is one seldom achieved and mastered. How often have you read a line and known the rhyme ending the following line long before you reach it? Even then it is often either trite or forced, and leaves you with tasteless doggerel.
Good poems depend on good patterns of rhythm, not in a boring strictness. Good poems depend on a pattern of sound (in the ear or in the mind) not on simple "sounds like" line endings. Free verse, free from the age-old traditions, needs to be the result of two things: the poet's mastery of form in all its classical presentation and his ability to carry pattern and sound beyond that captured by such forms, not away from it.
Two old adages come to mind. First, to achieve freedom, you must first know your bonds. And second, it is better to make a small step forward than to slide a long way off the trail.