I have a large text file (~6kB) that forms part of my challenge. How do I provide a link to download it instead of embedding the text in my question? I believe I have seen other questions do this but I don't have any examples.
Host it elsewhere
And provide a link to where it is hosted.
Tons of sites let you do this for free. A very simple option is Pastebin.
Google docs, Github, and Dropbox are some other common options that come to mind. Though for those you'll need an account.
If you specifically want a download link, these kind of sites usually have an option for that (example). Though I'd advise against that here. I'd personally prefer to be directed to the raw text; I know how to download if I want to.