Put the purpose first
Begin with the reason for your message. Are you asking a question, sharing an update or inviting someone to an activity? One clear opening sentence helps the reader know what matters before they reach the details.
Include what someone needs to act
For an invitation, check the date, time, place and contact route. For a question, explain the relevant context and what answer would help. Keep personal details out of public groups unless sharing them is necessary and the person has agreed.
Read once before you send
Check names, links and numbers. Remove words that repeat the same idea. If you are forwarding information, check where it came from and whether it is current. A short, accurate message is more useful than a long message that leaves people guessing.
Pass something you learned on to someone else.