Just double-click the lombok.jar file you've downloaded to install lombok into
your IDE. lombok.jar is also the jar you use as a project dependency
(include it in your classpath when compiling with javac or add it to your project
library list in your java IDE). It's the only jar you need!
If double-clicking opens winrar or some other archiver, go to the command line and run
java -jar lombok.jar to start the installer.