Start SQL Server Management Studio or via third-party software, but only in case a guide below didn't assist you, good luck!
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Click the “Start” button. Move the mouse cursor to the “All Programs” menu, then find and click “Microsoft SQL Server” to open a list of SQL Server programs.
Click “SQL Server Management Studio” to open the Connect to Server dialog box.
Select a server on your network. Set the “Authentication” pull-down list to “Windows Authentication” and click the “Connect” button.