All guests over a certain age get a magic band if they are staying in, and listed on, a room reservation, whether that room is a DVC room or a normal hotel room, or paid in points or cash. When you link your reservation number to your MyDisneyExperience account, you will be given a list of "tasks" to perform. One of them is customizing your magic bands. You can choose from a number of solid colors, and put names or sayings on the bands of your choice. About a month before you arrive at WDW, you will get a notification when the magic bands will ship and a tracking number.
When your advance dining reservation window opens up at 180 days, MyDisneyExperience will notify you. To make ADR's, you'll need a credit card (for the guarantee). You don't need tickets to make ADR's.
When your Fast Pass Plus window opens, MyDisneyExperience will notify you. In order to make FPP reservations, you will have to link tickets for your party members in MyDisneyExperience. As hakepd noted, you can buy tickets from Disney direct,
Undercover Tourist, and other places (I used ticketsatwork.com). You'll get a ticket number. You'll enter the ticket number into MyDisneyExperience and it will distribute the tickets as appropriate to the members of your party.