You can edit the last keyboard macro by typing C-x C-k C-e or
C-x C-k RET (kmacro-edit-macro). This formats the macro
definition in a buffer and enters a specialized major mode for editing
it. Type C-h m once in that buffer to display details of how to
edit the macro. When you are finished editing, type C-c C-c.
You can edit a named keyboard macro or a macro bound to a key by typing
C-x C-k e (edit-kbd-macro). Follow that with the
keyboard input that you would use to invoke the macro—C-x e or
M-x name or some other key sequence.
You can edit the last 100 keystrokes as a macro by typing
C-x C-k l (kmacro-edit-lossage).