Executing Stored Procedure using Command Object

I defined SP in the SQL Server like following.

IF OBJECT_ID('Sales.GetCustomerOrders', 'P') IS NOT NULL
        DROP PROC Sales.GetCustomerOrders;
GO

CREATE PROC Sales.GetCustomerOrders
        @custid         AS INT,
        @fromdate       AS DATETIME = '19000101',
        @todate         AS DATETIME = '99991231',
        @numrows        AS INT OUTPUT
AS
SET NOCOUNT ON;

SELECT orderid, custid, empid, orderdate
FROM Sales.Orders
WHERE custid = @custid
   AND orderdate >= @fromdate
   AND orderdate < @todate

SET @numrows = @@rowcount;
GO

I want to make client code including SqlCommand, SqlParameter, InputParameter and SqlDataReader.

How to get data and put into List<string>?