First and foremost, if you don't know what an account contact is, please refer to our article What are account contacts? as it could affect your decision to choose to implement this feature.
To add an account contact to your account, follow the instructions below.
You now know how to add contacts to your account. Please remember that all contacts you add are liable for the same user restrictions, limitations, and terms of service as your account, so do not sign up any contacts without their expressed permission / acknowledgement.
You may add contacts at anytime, and without any limits. Make sure you only add individuals you truly trust with your account, as adding the wrong individuals could place unnecessary risk to your account.