If you are writing the code just for your own use (i.e. not for general publication) then there may be no need to put the code into a library. It may be sufficient to put it in a .ino file or a .h file that you include in your program. That way you avoid the complexities of complying with the library system.
Of course if the purpose of the exercise is just to lean how to create a library, then please ignore my comment.
...R
PS. If you are planning to publish your library please write some very clear documentation to go along with it.