Murder your darlings

There was a Beat Generation attitude to writing which was "first thoughts, best thoughts". In my thirtieth year of writing I more than ever liken poetry to sculpture - you chip away anything extra, anything lumpy until you are left with the finished form.
Since late 2009 I've been working towards realizing my fifth volume of poetry, entitled "Personal Weather". I say to myself that I don't want any passengers in the collection, any poems that let the team down. In the last three months I've printed out all the poems intended for the manuscript and then given them a hard look. This scrutiny has resulted in a dozen poems being deleted. I'm now faced with "replacing" those deleted poems. I've shift my self-imposed deadline back now several months. I'm pleased that I got rid of those dozen poems. After a break of not looking at them, then re-looking at them, I could see they were either skeletal, didn't have enough going for them, that I was to a degree repeating subject matter and character types.
I promote being ruthless with your own work. What I find holds people back is that they don't write often enough, don't face the blank page often enough. They say they are waiting for inspiration or only write when inspired - this results, at best, in five poems written in a year.
Raise the bar for yourself. Face the blank page each week. Make it a life priority. Trust that there's material in your heart, mind and bones that you don't know is there until it comes out of your fingertips on the keyboard or out of your pen. Face the blank page, calm but focused. Negative thoughts about your writing capabilities, "I have no ideas", "What can I possibly write about?", "Everything I've written in the last month is crummy" will freeze you up/block you.
Relax. Trial some words on a page. If you don't like them, no big deal. Try out some more.
Even if you spend eight hours at that keyboard/writing desk and you're not happy with anything you've written, you've cleared away debris and cobwebs. I believe no writing time is wasted time. You've got to dig away a lot of dirt to get to the gold.
Persist. Continue. You want to be a writer. Charles Bukowski said "A writer should be writing".
Writing is not easy. Some days it comes easier than others. Stay in training by writing regularly,
keep that mind supple and give it nourishment by reading and reading, going for walks thinking about the big questions too "Why are we here? What is our/my purpose? Is there an afterlife? What is a human being?
Write about your life. Pivotal, significant moments in your life. A poem about a parent. A poem about your childhood - how it REALLY was - not a soft focus fantasy version of it. Poems about what you observe. Poems about what you think about. Tell me what it's like to be you but don't complain or rant in a poem. You have your senses, your mind, your personal history, all taking things in, sifting and reconsidering. Go for it.