I am defining a particular keyboard macro quite often, so I thought that it might be handy if it was automatically available every time I load Emacs.
How can I do this?
How about the save keyboard macros section of the manual?
C-x C-k n
Give a command name (for the duration of the Emacs session) to the most recently defined keyboard macro (kmacro-name-last-macro).
C-x C-k b
Bind the most recently defined keyboard macro to a key sequence (for the duration of the session) (kmacro-bind-to-key).
M-x insert-kbd-macro
Insert in the buffer a keyboard macro's definition, as Lisp code.