Connecting to Facebook will change your Player Name and Avatar to the one used with Facebook (name using only first name and last initial).

If you are not connected to Facebook or do not wish to do so, you can choose your own Player Name and pick from in-game Avatar options. To access them, go to your League page.
 
To change your Player Name:
  1. Select the "Members" tab at the bottom of the screen
  2. Tap on yourself in the League roster (you will be the one highlighted with a purple background)
  3. Select the edit icon at the right-side of the red banner
  4. Input your desired player name or tap on the dice button for randomized suggestions
  5. Select "Confirm"
To change your Avatar:
  1. Select the "Members" tab at the bottom of the screen
  2. Tap on yourself in the League roster (you will be the one highlighted with a purple background)
  3. Tap on your current Avatar
  4. Scroll through the in-game Avatar options
  5. Once an Avatar is tapped, it will immediately be applied. If you want to make a different selection, repeat steps 3 and 4.