Workflow Requirement on sales order change

Hi all,

I have been assigned to a workflow object where if there is a change in sales order VA02 the mail should be send to external gmail id and SBWP ( sap inbox ). Now using tcode SWELS, i have captured business object that is BUS2032 and in that business object there is a event changed and method is also there. Now how should i proceed with this development ? Where i will have to have mention my workflow no that whenever any change in SO , the workflow get triggered? I have created node HTTP in SCOT tcode ...still mail is now going to gmail id,why is it so?

Please help me out

Thanks

Parag