Best Way to Implement JavaScript for a Page?

I have a page I want to make an accordion type navigation on a page itself. It requires a .js files to be referenced. What is the best way to do this? Should I put it into the theme and reference it there? Upload it as a file to the page and reference it there?

I’m not real well versed on this type of thing, but this page should be the only thing that needs the .js file.

Please let me know if you have any suggestions. Thanks in advance.