Program security system with Home Link?

Hello all, I read through the manual and searched on priuschat but still have a question. I have a friend who is staying with me for a couple of months and I have given her my ADT remote to use so I don't have to worry about her accidentally setting off my alarm. I was trying to figure out how to program my home link mirror with the ADT remote so I am not without a remote. The ADT remote has 3 distinct buttons- arm, off, and stay. I only need to use the arm and off buttons. I am guessing that I will need to program two seperate buttons on the mirror for these two features? Has anybody done this already? Is there anything special I need to know when I do this? Thanks!