DocuSign Custom Object setup to store the completed documents in salesforce

we are implementing the Docusign - salesforce Integration using Docusign Legacy E-signature Application. I would like to understand how the custom connect object will work and once we complete the documents I would need to store the completed envelopes to the custom connect Object. Let's say if I initiate the DocuSign from an account I need to store in one custom object and If I do Initiate DocuSign from an opportunity I would like to store my documents on another custom object. Please reach out to me if there are any professionals in this area.