Opening up the userscript.user.js
file from the root of the repository you'll be presented with the code for the userscript, the main two lines you need to edit are:
var baseUrl = 'http://your.archive.url.com/';
var key = 'changeme';
For baseUrl
you'll want to change it to whatever URL your local server is addressed to, the case of the Windows and Linux guides it's https://exhen.localhost/
.
The Vagrant guide it is meerly just https://localhost/
For key
this is the value you configured in your config.json
file.
Now to install the userscript just drag and drop it into your browser, this will open it prompting what ever userscript engine you have to ask if you want to install it.
Or you can click File -> Open and then open the file, either way the file will be open.