How do I read a .man file that's not on my manpath? I know I had a command for this, but now I don't remember, and I can't find the right switch in the man pages for man.
You can try to read your file by doing
man path_to_file
as man will treat the given argument as a file if it finds a slash / in it.
For instance
man ./my_test
will open the my_test file, while
man my_test
will look in the standard manual for the given command.