This might be a silly subject for a website dedicated for progress. But maybe learning how to write poems is someone's idea of progressing! And since I'm quite the expert on writing poems (not), having (self-)published a poetry collection myself and all, I think I know what I'm talking about. So if you're interested in poetry writing, here are my tips.
One. It's not as much how to write a poem as it is when to write it. I've found over the years that the quality of my poetry increases dramatically when I write during heartbreak. Or an emotional state in general, happy or sad. I have no idea why it works this way - perhaps we tap into something artistic in our subconscious more during those moments. So if you find yourself staring at a blank page with a writer's block, just stop right now and go do something else - until you feel exceptionally depressed or exceptionally joyful and return to the blank page. You'll see it won't be blank for long.
Two. Fake it until you make it. Chances are your very first poem isn't pure gold. At least mine wasn't. Looking at my first poem years later I can see how naive and amateur I was back then. I thought I knew how to write a poem - until my style developed and I could no longer recognize the person behind the first piece.
Three. And this is important. It doesn't have to rhyme. People seem to think poetry has to rhyme - since most song lyrics are poems and they rhyme - but this is absolute hogwash. You can write rhyming poems, you can write non-rhyming, free poems (so-called contemporary poems, that is), you can write all one stanza, you can have 500 stanzas, one line each. There's really no limit. You can do it anyway you like.
Four. If you feel emotional yet still don't know what to write about (this is very rare since you usually feel inclined to write about what you're feeling emotional about), take random words and play around with them. It might work out nicer than you think.
There you go, my handiest tips for poetry writing. Try it out. I find writing poems one of the most fun activities in life.