Apex Toolkit -- Modifying Recipient Routing Order

You can specify Recipient with Signing Order:
 

dfsle.Recipient myRecipient1 = dfsle.Recipient.fromSource(
                    'Signer One' , // Recipient name
                    'signer1@abc.com', // Recipient email
                    null, //Optional phone number
                    'Signer 1', //Role Name. Specify the exact role name from template
                    null).withRoutingOrder(1); 

dfsle.Recipient myRecipient2 = dfsle.Recipient.fromSource(
                    'Signer Two' , // Recipient name
                    'signer1@abc.com', // Recipient email
                    null, //Optional phone number
                    'Signer 2', //Role Name. Specify the exact role name from template
                    null).withRoutingOrder(2);