What is a process of thinking about what you want to say, how to say it, and sending a message

The process is called elocution.

Explanation:

The process of elocution in general would involve a few of these things that are anticipated by the reasons one would have for communicating and the way it actually gets communicated to the people intended:

It is basically about

- - What you want to say

_ How you want to say what you want to say in that what medium and what manner to use

- - Sending a message in that how is it that one would want to get their message across.