Writing for the internet or a newsletter is something totally different than writing a book. In any comunication, you need to use different forms of communication, to be succesful at getting the message through. On the internet, use as little words as possible. Offline, you may be more prozaic: people still tend to find it hard to read from screans.
It is always good to have somebody else read your texts. They will find mistakes that you overlooked while writing or simply because you read with only half an eye, as you already know what you're trying to say.
Some tips for any writing:
The Burkina Faso Platform sends out newsletters at irregular intervals. These are often written by the board members, but as the person who submits the actual letters, I usually try to find the time to send in a reviewed/edited version. Usually most changes are accepted after which the newsletter is finalized and ready for me to send.