how to get working date loop? I need each days time for last 6 months any suggestion?

Try:

WITH 
         t4 AS (SELECT n FROM (VALUES(0),(0),(0),(0)) t(n)) 
        ,t256 AS (SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) AS num FROM t4 AS a CROSS JOIN t4 AS b CROSS JOIN t4 AS c CROSS JOIN t4 AS d)
SELECT * 
FROM [dbo].[FactInternetSales] 
WHERE OrderDate  IN  (
        SELECT DATEADD(day,-num+1,CAST(GETDATE() AS date))
        FROM t256
        WHERE num <= 180);

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Dan Guzman, SQL Server MVP, http://www.dbdelta.com