To elaborate a bit more on ravenclawtrekkie's response, if you purchase your military salute tickets ahead of time, you will receive an exchange certificate that looks like this (I believe the 2016 ones are blue, not green.):
The number where I put the black bar is what you enter into your
MDE account, to be eligible to pre-book fastpasses.
Then when you arrive at WDW, you have to activate your tickets by going to a Guest Services or Ticket window anywhere on property (not just the places listed on the front). We did it at Disney Springs the night we arrived, since we were not planning to enter a park until the next morning.
To activate, the military member has to show ID, and the other guests may be required to do so as well, whether they are military or not. Some people report that not everyone has to be there, but technically it is required. You actually do not need the exchange certificate, if everything is linked in your MDE, but it's good to have it as a backup.
One more thing, just to make sure it's clear, you are not linking tickets to your magic band. Nothing is "on" a band. It is just a link to the information in your MDE account.
Have a great trip!