User guide contributions
Contributions to the guide would be great. Please, please make some!
For small corrections such as typos, spelling, grammar, and factual in-accuracies please email the author. For larger contributions - additional chapters, translations and so on, please consider using LyX to edit the document source and submit patches to the author.
Getting the document source
The source for the user guide is available by anonymous CVS from the sourceforge project pages.
I made a silly decision. I started to use the development version of LyX (1.4.0pre). It seemed like such a good idea at the time - the development version contains some cool new functionality that could be useful (change tracking, branches etc.), and it's been out for quite a while and seems pretty stable.
The problem is that the user guide .lyx files that have been edited using the development version of LyX are not editable with the stable version of LyX, and that there are no binaries for download (i.e. you have to compile LyX from source to use the development version).
Anyhow, you can get the source from the LyX website. I hope 1.4 will go gold soon and there will be binaries for all platforms.
Submitting a patch
Once you've got LyX and the guide source, edit the files and make a patch file using diff. You can find a nice tutorial about how to do this here.