Start using Zoho Sign Qodex Collection
Register on the Zoho Developer Console and generate a client by visiting Zoho API Console and generate client secrets with scopes
ZohoSign.documents.ALL,ZohoSign.templates.ALL
.Generate refresh token using client secrets by visiting here.
Add generated client secrets and refresh token as a current value in collection variable, which will auto-generate access token once it got expired after an hour.
Check out Zoho Sign's API Documentation and [Qodex Documentation]