create new user in SQL Server 2008 with the help of query

how to create new user in SQL Server 2008 with the help of  query...????

i have to already query but that is not working 

USE master
GO
CREATE LOGIN [con1] WITH PASSWORD=N'test', DEFAULT_DATABASE=[master], CHECK_EXPIRATION=OFF, CHECK_POLICY=OFF
GO
EXEC sp_addrolemember 'sysadmin', 'con1'
GO

here is give the error "The role 'sysadmin' does not exist in the current database."