We have a user manual available here in the Bertini_real repo on GitHub. It was written primarily by Notre Dame undergraduates Pierce Cunneen, Elizabeth Sudkamp, and Chris Lembo. Source is also included in the repo -- you can compile it if you have tex installed. Write to Dani Brake if you want to compile the manual for any reason.

Documentation for the source code for Bertini_real is built from source using the excellent Doxygen, and is available at the subdomain doc.bertinireal.com. You can also build it yourself if you have doxygen installed.