Code:
DECLARE @file varchar(70)
SET @file = N'D:\MuOnline_'+REPLACE(REPLACE(CAST(getdate() AS varchar), ' ', '_'), ':', '_')
SELECT @file
BACKUP DATABASE [MuOnline] TO DISK = @file WITH INIT , NOUNLOAD , NAME = N'MuOnline backup', NOSKIP , STATS = 10, NOFORMAT
you can edit file location (SET @file = N'D:\MuOnline_'+REPLACE(REPLACE(CAST(getdate() AS varchar), ' ', '_'), ':', '_')) or make it work with any database ([MuOnline])
save this as step in SQL Server Agent.
Older file will not be overwrited when creating new one so you will need to delete old databases sometimes