How to Open the SDK Manager

1. In Android Studio, click SDK Manager in the toolbar.

2. In Eclipse (with ADT), select Window > Android SDK Manager.

3. On Windows, double-click the SDK Manager.exe file at the root of the Android SDK directory.

4. On Mac or Linux, open a terminal and navigate to the tools/ directory in the Android SDK, then executeandroid sdk.


Resources:

http://developer.android.com/google/play-services/setup.html#Install