poetry has many diffrent styles. it's like art. doesnt have to have deep metaphores, rhymes, or even rhythm. Its all up to you.
First off, guys usually arnt that big on poetry. just try to keep it straight forward so he wont get confused.
Second, dont worry if it doesnt seem good enough to you. You are your own worst critic. Just keep writing and you can always go over it and make little changes later.
Good luck, hope he likes it. Feel free to ask about any specific parts you may be struggling with.