Changing the CommandTimeout in SQL Management studio

If you are getting a timeout while on the table designer, change the "Transaction time-out after" value under Tools --> Options --> Designers --> Table and Database Designers

This will get rid of this message: "Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding."

Changing Command Execute Timeout in Management Studio:

Click on Tools -> Options

Select Query Execution from tree on left side and enter command timeout in "Execute Timeout" control.

Changing Command Timeout in Server:

In the object browser tree right click on the server which give you timeout and select "Properties" from context menu.

Now in "Server Properties -....." dialog click on "Connections" page in "Select a Page" list (on left side). On the right side you will get property

Remote query timeout (in seconds, 0 = no timeout):
[up/down control]

you can set the value in up/down control.

Right click in the query pane, select Query Options... and in the Execution->General section (the default when you first open it) there is an Execution time-out setting.