How to create a new project in cocos2d?
After installing cocos2d, take xcode go to File -> New Project. From the window which appears, select the cocos2d version you have installed from User Templates on left panel. Select Cocos2d Application on the right panel and select Choose.
Give a name for your project and save the project.
After the project is open, you run the project using the Build and Run option.
You should get a Hello World screen with black background like this.
Now your system is ready for creating cocos2d projects.