I'm fairly new to Docusign and have a fairly basic question.
Assume I have my Integrator Key, etc. already set up.
A user will select a file in my application and then select "Send for signature," and all my application will do is initiate the esignature process and send the file to Docusign. My application won't know whose Docusign account it is or who the recipient(s) will be.
Then a new window (or an iframe) will appear, hosted by Docusign, where the user will be asked to enter their Docusign username and password (or to register if they don't have an account), and then the user will complete the rest of the process (identify the signature block, indicate who needs to sign, etc.)
This is similar to how Box.com integrates with Docusign. Most of the API calls I have seen request the recipient's information. All I will have is the file itself, and the information that identifies my application making the call.