You will need to download a FTP. I personally use Filezilla. Create a folder inside your USB hdd titled PS3 and create another folder within that titled UPDATE. Place the Geohot CFW file inside the UPDATE folder. Plug in your USB hdd into your PS3 and do a manual update. You'll see 'Geohot CFW' or something as your only option and go through with it. When finished, your system will turn off and beep 4-7 times. Turn it back on and you'll see a 'install package' on your XMB underneath Game.

I use blackbox as my FTP server. If your transferring everything from your external, just swap out the necessary files except the .eboot and make sure the names match up with your .pkg names (so it knows where to find the data).