When "resending" a SignRequest document, keep in mind that it will send again to all parties involved. It is not currently possible to resend a SignRequest email to only one email address.
If you would like to resend a SignRequest to a different email address, first go to the 'My Documents' section.
If you have accidentally sent a SignRequest to the wrong email address, you will first need to 'Cancel' that SignRequest. This can be done by clicking on the document in the 'My Documents' section, then clicking 'Cancel document'.
To resend the SignRequest to a different email address, click 'Save as Template'.
Then go to the 'Templates' folder and click 'SignRequest' on the template you just created.
Finally, enter the new email addresses, and click 'Send'.
For a visual tutorial, please see the following video: