First, decide:
•Who is your news audience?
•Why might they be interested in this?
•What, therefore, is the most important news fact?
•What, therefore, are the important secondary facts?
Then:
•Write the headline first
•Make sure the 5 Ws are in the first one or two paragraphs
•Follow the inverted pyramid news writing structure, so the least important details are at the bottom
•If you can, try to follow the Bloomberg four paragraph lead – this insists that you have a strong quote in the third or fourth paragraph, which is good practice, and that you try to write a nutgraph