Hi Karen, thanks for stopping by with your question.
Glad to hEAR you purchased
Memory Maker. It is a great acquisition! Disney Photopass Photographers will be located at the best spots taking the most beautiful photos of you and your family.
If you bought Memory Maker in advance, it will be activated when you download your first photo on MyDisneyPhotoPass.com or My Disney Experience App, it means when you start taking your pictures.
Remember, if you are getting the discount when purchasing Memory Maker in advance, you will need to wait three days before you start using it at WDW.
Hope this information helps your planning. Let us know if you have further questions.
Have a wonderful day!
Gina V.