This poem has an intimate, conversational tone to it. It mentions everyday things—like socks and coats and houses—and it uses language that's simple and conversational. It's as if the speaker is actually just chatting to his lover. Let's take lines 1-6 as an example:
I am offering this poem to you,
since I have nothing else to give.
Keep it like a warm coat
when winter comes to cover you,
or like a pair of thick socks
the cold cannot bite through.
As we can see, there are no big, fancy words here. The diction is simple. So it really does just sound like everyday speech, like a guy chatting away to his girlfriend.
That said, we can see quite a bit of alliteration going on here, too. The lines, "Keep it like a warm coat/ when winter comes to cover you" repeat the W and C sounds quite a bit. And the lines "like a pair of thick socks/ the cold cannot bite through" give us some hard C consonance. So the poem sounds conversational, but within that conversational tone we can also identify some clear poetic echoes. That seems fitting, don't you think? In a poem about lovers, even the sounds of the poem are finding themselves paired up.