Your piece needs to be built on messages that engage your defined audience encourage them to respond as you want them to, to achieve your objectives. Anything that doesn't contribute to these ends has no place in it.
Be ruthless. Resist the temptation to tell your readers that your company won the Award for Excellent Employee Relations three years running, unless it will materially help with engaging or persuading them. Focus on the issues that your readers actually care about, and the ways in which your offering will improve things for them.
Get these three areas right, and you'll find the process of writing much easier. With a clear understanding of what you're after, who you're talking to and what you need to say, it's much easier to stay on track, to stick to your core message.
Once you've drafted your copy, proofing and editing it will be that much easier too: use your planned objectives, audience and message as a yardstick to check what you've written.
Get the foundations right, before you write: objectives, audience, message.
