1. Install the Xdebug helper extension for Chrome from the Chrome webstore:
Read the instructions and click Add:
Xdebug helper is installed!
2. Open PhpStorm and enable listening to debug connections:
3. You are ready to initiate a connection from the browser side. Use the bug-styled icon near the right end of the address bar to initiate a debugging, profiling or tracing session:
4. Usually Xdebug helper works without any configuration, but you can always change the IDE key and get help in Chrome's Settings | Extensions | Xdebug helper | Options: