You open the Control Panel by clicking Start -> Control Panel. If it’s not on your Start Menu, it’s easy to add:

Right-click the Start button and choose Properties from the pop-up menu.

On the Start Menu tab and click Customize.

Click the Advanced tab.

In the Start Menu Items list under the Control Panel section, select either Display As Link or Display As Menu. The former (the default) simply displays a Control Panel option on the Start Menu; the latter displays the Control Panel option with a cascading menu providing direct access to each Control Panel applet.

Click OK twice to exit the dialogs.