When you want to create new Sales Orders in MS Dynamics NAV, the obvious choice is to publish the standard Sales Order Page (Page 42) as a Web service and use this Web service to insert the new Sales Orders in NAV.
But you need three Web Service calls to create a completely new Sales Order:
On our side, we have simplified the process so you can create 1 Sales Order via a single transfer. Check this article and learn more about it.