Question

What are the basic steps to Decode and Encode a particular message ?

Example: Figure.

Answer 1

figure ....

Answer 2

Well, the very basic steps are to take the message, put it into some sort of algorithm, and get out a different form.

All the magic happens in the algorithm. Is it going to use a one time pad where you do modular addition? How about a matrix transformation using an invertible matrix? Etc. See some references here:

http://www.cs.utsa.edu/~wagner/laws/pad.html