It's that excitement you need to tap into. Of course you’re nervous and feel a lack of confidence. That’s natural. But the excitement is natural as well. And it’s the excitement your body is giving you that you can rely upon. That excitement is pumping your heart and your blood vessels and that is what gives you the rhythm for your work. This is what most writers of poetry don’t understand but that you appear to feel naturally. Take advantage of it.
When you are writing about something and you think you have all the words you want on paper, tap into that feeling of excitement, sit back, close your eyes, and almost meditate on your pulse and heartbeat. Listen to it. If you want, stick your fingers into your ears so you can hear it better. Breathe down deep, but not so deeply that you begin to relax and loose the feeling. Let that pulse move through your body, every part of it, all the sensual parts. Let it move around and feel it deeply for a few minutes at least.
Now. NOW. Go back to that piece of paper where all the words are written. NOW put those words into some order but follow that rhythm you’ve felt. That natural rhythm of your body’s excitement after having written those words that flowed from your true feelings.