Using -prune option of find to ignore hidden directories

[Richard Owlett <rowlett@cloud85.net>]

The man page for find confuses me.
Looking for explanatory material I found and tried to follow examples in 
http://mywiki.wooledge.org/UsingFind#A-prune .

I tried
  find /home/richard \( -type d -name .* -prune \) -o -atime -42 -print
and
  find /home/richard \( -type d -name .* -prune \) -atime -42 -print
unsuccessfully.

Each got an "find: paths must precede expression: .." error

HOW?
TIA