You don't. You could try overleaf or some wysiwyg editor for LaTeX, but both need some getting used to and at least a minute amount of effort. Overleaf probably has the lowest barrier of entry (0 set up required), but is a paid service.

It depends on what sort of collaboration. For things on which I was the sole author, like my dissertation, I leveraged the miracle that is pandoc. Every email my advisor got from me was a perfectly formatted Word doc with a flawless bibliography and he never had to learn what the hell LaTeX is.

But if you have multiple contributors going back and forth, or need to keep long-lived discussions in the track changes panel, you’re better off not trying to teach others a new tool. Unless they have a genuine interest in it, in which case the WYSIWYG editors can be fun.

Markdown and pandoc are like match made in heaven for this. If you didn’t know, Markdown is plain text file, has a simple syntax for formatting (that gets carried over when you use pandoc), supports LaTeX equations and can attach metadata as yaml part on top of the file (gives custom usability when pandoc works on it) and supports citations w/ a bibliography file. And pandoc is document converter between multiple formats and can produce word files, PowerPoints, html file, latex pdfs (book, report, Beamer presentations) etc. You can also provide a template for pandoc to work with and it produces in that format. Not to mention since it’s plain text, you can apply git version control and also use make files to iteratively compile new outputs.

There is also RMarkdown (or it’s newer successor Quartro), which is same markdown pipeline but also can compute codes inside a section and attaches the result to the markdown file and does the whole pandoc thing afterwards. Think of it as like Jupyter Notebook style of literate programming with Markdown. Here’s a demonstration of its capabilities. https://youtu.be/_D-ux3MqGug

Assuming your colleagues can work with git but not LaTeX, you can set up a git repo with just markdown files and collaborate on that and have a makefile or docker container to get the final word or pdf generated. Here’s a good example of an pandoc makefile https://gist.github.com/kristopherjohnson/7466917

In Worst case scenario that they only work with word files, you can generate one from your markdown files and share with them and pull down the changes they sent you on the word document.

P.S. I assume Org-Mode can also substitute Markdown here in the pipeline. But I haven’t committed to it, so I’m not fully sure.

IMO LyX is way simpler than LaTeX for basic stuff, but because it is literally not Microsoft Word I couldn't really use it to collaborate with people this semester, let alone convince them to work on a full LaTeX document. LyX would be the way to go if my colleagues were even remotely interested in learning about literally anything. You can lead a horse to water, but you can't make it drink...