Follow these steps to limit the amount of SQL Server memory you can use:
1. Connect to the SQL Server Management Studio console by typing ssms in the Run window.
2. Enter the required information including Instance (Server Name), username and password for Instance connection and click on Connect button.
3. Right-click on the Instance you want, select Properties.
4. Click the Memory option on the left side of the screen.
5. In the Maximum Server Memory (in MB) section, enter the desired memory space into MB and click OK to save the settings.