How can I send a private message to someone on Facebook?
To send a message:
- Click Messages at the top of the screen.
- Click New Message.
- Start typing a name into the “To” field. Names of friends will appear in a dropdown list.
- Select the person or people you want to message.
- Type your message, then press enter to send.
The following link will also give you more detailed instructions:
https://www.facebook.com/help/154917244574299