1. Download a package and extract it (since the package is contained in a sub-folder you can extract directly using "Extract here" without causing a mess)
  2. transfer the extracted folder into any USB storage device formatted into Fat32 filesystem
  3. Launch the installer with your Playstation 2 console. this is usually done via uLaunchELF (if you don´t have means to execute it, take a look at FreeDVDBoot, find a friend with access to uLaunchELF or buy a pre-installed card and install from scratch).
  4. Once you land into the installer menu, choose the install mode and wait untill is done. for more information regarding install modes, please take a look here
  5. you´re good to go, have fun!