How to: Set an Instance of SQL Server to Start Automatically (SQL Server Configuration Manager)
During setup, Microsoft SQL Server is normally configured to start automatically. If this was not done, you can change that setting at any time.
To set an instance of SQL Server to start automatically
On the Start menu, point to All Programs, point to Microsoft SQL Server 2008 R2, point to Configuration Tools, and then click SQL Server Configuration Manager.
In SQL Server Configuration Manager, expand Services, and then click SQL Server.
In the details pane, right-click the name of the instance you want to start automatically, and then click Properties.
In the SQL Server <instancename> Properties dialog box, set Start Mode to Automatic.
Click OK, and then close SQL Server Configuration Manager.