php环境变量不起作用

I've followed tutorials and answer here on Stackoverflow, but I still can't access php.exe from command line.

All I get is:

php is not recognized as an internal or external command...

How can I make php.exe accessible from anywhere in the command line?

What else can I try to execute PHP from command line?

Path should be

C:\wamp\bin\php\php5.4.12

without php at end