You'll need to establish an account after installing the Fitbit app. You'll be asked what sort of Fitbit setup you have, so select your model from the drop-down box. Fill in your information, including your name, birthday, height, weight, and gender, after entering your email and password. Then, after agreeing to the terms and conditions, click "Create an Account." You can sync and link your Fitbit after you've created an account. This is accomplished by enabling the app to locate your tracker. It will then send a 4-digit number to your Fitbit, which you must enter into the app.