The AVD Manager provides a graphical user interface in which you can create and manage Android Virtual Devices (AVDs), which are required by the Android Emulator.
You can launch the AVD Manager in following way:
Navigate to your SDK's
tools/ directory and execute
$ android avd
Open Android VDM and click new to create a new virtual environment.
Note: If Hardware keyboard is selected, the keyboard will not show up on the screen of emulator as it does on devices which may result into failing tests
You are able to customize your virtual environment. Use the image above to create a general virtual environment.
$ adb devices -l
Shows all physical devices connected. Depending on your device you might need the proper OEM USB driver.