1. Download Eclipse IDE for Java EE Developers
2. Extract the archive file to where you want to install Eclipse.
3. Open Eclipse, Go to Help->Install New Software...
4. Add Symfony-2-Eclipse-Plugin repository: http://pulse00.github.com/Symfony-2-Eclipse-Plugin/
5. Install All of them. (PDT Extensions, PHP Development Tools, Symfony, YEdit)
6. Add Eclipse Color Theme plugins repository: http://eclipse-color-theme.github.com/update
7. Install Eclipse Color Theme
8. Download Eclipse Symfony2 theme
9. Go to Window->Preferences->General->Appearance->Color Theme , and install the Symfony2 theme.
10. ALL DONE! ENJOY Symfony2!
ex1. Go to PHP->Code Style->Formatter(PDT Tooles) Change Active profile to "Symfony [built in]"
ex2. Edit theme color in Twig: Normal, String
ex3. Edit theme color in YEdit: Scalars, Documents, Default