The simplicity of the poem is surprising considering that it is an ode, which traditionally is a solemn and elaborately structured poem. Choral odes of ancient Greece (so called because they were sung by the chorus during the performance of a drama) had a three-part structure of strophe (literally "turn"), antistrophe ("turning the other way"), and epode ("added song"). This structure marks a turn from one intellectual position to another and then a recounting of the entire ode subject. Neruda to some extent follows the conventions of the ode. He chooses a subject to praise (albeit one that is traditionally not the subject of such lavish exultation). His first "turn" is to celebrate the socks' beauty by comparing them to jewel cases, sharks, and so on. He "turns the other way'' by saying what he did not do with the socks. Finally he offers a moral to the story by explaining obliquely why these socks are worthy of his admiration—and why he is in fact worthy of them.
In "Ode to My Socks," as again he does in his odes, Neruda uses very short, irregular lines. This emphasizes their simplicity, forcing a slower reading and making the poems sound more like natural speech and less artificially "poetic." But they are very clearly poems from their structure.
This poem is written in free verse, a detailed defintion of which can be found at the website listed below. Free verse has no rhyme or meter; it is a simplistic and straightforward form of expressing poetry, without having to manufacture a certain cadence or stylistic effect. This fits closely with the pure simplicity of Neruda's message. In a poem about a mundane object, Neruda is able to capture the beauty in a lack of "embellishment". The socks have beauty because they are useful, not because they look good. As is the same with this poem, which in free verse serves its purpose without "putting on" poetic airs.