To begin the process, you would have to install the most recent version of Node.js (https://nodejs.org/en/). The instructions should come along with the Node.js setup pop-up. This will install npm with Node.
From here, you can install yarn. This of which may be done by entering the following into the Windows Cmd Prompt:
npm install --global yarn
Now identify and move to the folder you are going to be using for your Cmd Prompt and type in:
npm init @open-wc
Wait patiently for everything to setup on its own. Once it's ready, options will appear on the screen. Make selections to: scaffold a new project, web component, linting, no (to typescript), the name of your web component ("hello-world"), review the file location (click yes to confirm it looks good), and then finally make a selection to "Yes, with yarn" for the dependencies to be installed.
Once this is in order, you should be all done!