After you enter your first and last name, you will see the following 

Pressing the skip button will display the following

You can invite co-workers to the system based on the number of user licenses available in your account. If you have not setup roles the default role you can invite people with will be the Admin role.

Custom Roles can be assigned and configured by your admin in the settings page. An admin will have access to all files that a restricted user might not and so on. 

The next step in the process allows you to import any data at setup.

Whether or not you have data to import you can get started by clicking the next button. You can always import data in the Accounts page at a later date. 

Once you have completed the final step you will receive a successfully authenticated notice and the popup will stop displaying and you can begin to execute all functions available to you role within the CRM.