The previous week before you come make sure to make a list checking everything you would probably need. A useful app is "Google Keep Notes", which you can use it wherever you go!
Granada has many things to see and many tapas to eat, so there is no time to lose! Be sure to check all the reservations requirements (Passport, appropiae clothing, the schedule didn't change...) and specially don't forget to enjoy the trip!
The weather is something that determinates everything when you travel, is the difference between behold the best sunset of your life or get really wet in the middle of nowhere. Check always the temperature, where you will go and if you're ready. Anticipation is everything!
Bear in mind most of the streets of Granada are cobbled, so believe me when I advice you to wear a proper footwear if you don't want to feel every single stone under your feet!