NET - Describe the steps to enable transactions in a web method

public class MyService : System.Web.Services.WebService
{
       [System.Web.Services.WebMethod(TransactionOption=TransactionOption.RequiresNew)]
       public string MyTransactionMethod()
       {
              // The transaction was successful...
              ContextUtil.SetComplete();
              return ContextUtil.TransactionId.ToString();
       }
}