All new accounts have paper accounts automatically created for them.If you opened your account before the automatic creation of paper accounts and you do not have a paper trading account yet, you can open a Paper Trading account in Client Portal/ Account Management:
Log in to Client Portal/ Account management
Click on Settings **followed by** Account Settings
Click the Configure icon (gear) next to the words Paper Trading Account in the Configuration section You will be notified to create a User ID and Password and click Continue.
Your request will be approved for processing. If we receive your request by 4:00 PM EST on any ordinary business day. It will be processed by the next business day under normal conditions. You will be prompted by email when the account is ready for trading. More information on the paper trading account can be found in our Users' Guide.

See also: What are the limitations of the paper trading account?
If you are not yet a client, see: How can I open a free trial account?