consume SOAP web service

How do I consume this SOAP web service? how do I add the request header?

https://www.eway.com.au/gateway/ManagedPaymentService/test/managedCreditCardPayment.asmx?op=CreateCustomer

REF: http://www.eway.com.au/Developer/eway-api/token-payments.aspx

The easiest way is to use .NET's built-in support.

In Visual Studio, right click on your project references and 'Add Service Reference'. Give it the service URL https://www.eway.com.au/gateway/ManagedPaymentService/managedCreditCardPayment.asmx and it will generate a proxy class for you that will do all the work. You can then just e.g.

var client = new eWayServiceReference.managedCreditCardPaymentSoapClient();
client.CreateCustomer(...);

Alternatively you can generate the proxy class from a VS command prompt using svcutil.