A custom library is helpful for organizing your project files. In this case where I want to share my design with my readers, the new/unique parts and footprints will be created in a new library called Programmer.
I created a new project called “Programmer” and saved it in a new folder called Uprogrammer in my home directory. I ran the eeschema from the KiCad dashboard. I then ran the library editor, selected a library. Then I created and exported a component and saved it to programmer.lib in the project directory.
I added this library to the KiCad library list, and then opened it to edit. I added the pins and made it look the way I want it in the schematic.
In looking for the pinout, I found out that there is a newer model of the ESP-12. It is the ESP12E It has 6 more pins that may be beneficial to the project. Click below to get this version of the library. I do expect this library to change as the project progresses.
Once that is done you then have to add the library to the project with preference library add , you then select your new lib and it will then become available to the project. You do the same thing with the modules by using the same sequence when using PCBnew.