1.Launch Eclipse and click Help > Install New Software....

2. Click Add....
3. In the Add Repository dialog, set the Name to "Force.com IDE" and the Location to "http://media.developerforce.com/force-ide/eclipse42" and click OK. (Use the same URL for Eclipse 4.3.)

4. If you want to install an older version of the plug-in (for example, if you do not have Java 7), be sure to clear the option "Show only the latest versions of available software.



5.Eclipse downloads the list of available plug-ins and displays them in the Available Software dialog
6.Check the box next to the Force.com IDE plug-in and click Next.


8. In the Review Licenses dialog, accept the terms and click Finish.
9. Eclipse downloads and installs the Force.com IDE and any required dependencies. When installation is complete, you will be prompted to restart. Click Yes.