Download
First things first, if you have not already installed KiCad onto your computer, do so now. The download links can be found at https://kicad-pcb.org/download/. The program should run on pretty much any computer but do note that it will take up around 5GB of space on your drive. Note that this tutorial written with KiCad version 6.0 in mind, and later versions might have slightly changed functionality that may render this tutorial somewhat outdated.
Start-up
Once KiCad is good to go, open it up. You should be met with a window similar to what is shown below. Note that there’s likely a few more things on my window compared to yours as I currently have an existing project open.
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Let’s take a moment to go over the points of interest on this window. On the title bar at the top of the window, you see the directory that the KiCad project file is in. To the left, you can see the project directory structure. We’ll go more into this later on, but for now know that the area will display all the important files and folders that are contained within the project, such as the board’s electrical schematics, PCB layout, and parts libraries. On the top bar, you have the usual buttons for things such as saving, loading, creating a new project, along with a few others.