Developers can go to HelloSign.com and create an account using the sign-up workflow.
Once the account is created, they will be able to login to HelloSign.com using the email address and password from the above sign-up.
Once logged into HelloSign, they can locate their API key on the API Settings page here. The API key can be located by clicking "Reveal Key", OR "Create Key" if the API key has never been created before. Screenshot below:
Here's what the API key looks like when you reveal it:
For the purpose of using the HelloSign API, the HelloSign API account is the API key associated with the email and password used during the signup workflow on HelloSign.com.