Everything you write should have a specific audience in mind. A mailing list may include just one coworker or everyone in the company. When you write always think about what you are writing from your audience’s point of view.
When you think about your audience’s point of view remember that they don’t know everything that you know. This is a classic tip for better writing and most engineers I know are really bad at it. Use citations a links to help your audience understand what you are talking about. Any time you mention a bug number, a specification, a previous conversation, a different article, or a different document link to it. A link takes up very little space in your document and will really help people follow what you are saying.