When writing a news update, make sure you have all the important facts that are relevant to your story. Write a list of everything you know about the subject matter and trim down what is not needed to keep your article short, clear and concise. Remember that your goal is to share direct facts and not your personal opinions so be careful about adding anything that could be deemed bias. Always have a strong concluding statement that restates your leading statement or indicates potential future developments in the story. Read other news articles or watch the news and see how the anchors wrap up the story to get an idea of what a good conclusion looks like.
Have an extra pair of eyes look over your work.