A macro is preferred over writing your response from scratch, as macros automatically apply several relevant tags to your ticket. Once you've applied a macro to your response, you can customize the text with specific instructions.
Springshare does an excellent job explaining how to apply macros to your response. Scroll down on the page to the section titled "How to use a macro."
Please note there are a few different responses for alums to address specific instances where the answer for an alumnus would differ from a student or faculty response. Those macros have (Alum) in the title.