1. SSH into your device as root by using the Terminal.app and issue the following command:
ssh email@example.com (You must replace 192.168.123.88 with your device’s actual IP address.)
2. Next, quit any applications on iPhone/iPod (Cydia if it is running), and issue the following Terminal command to start installation: dpkg -i /tmp/”name.deb”
(Replace “name.deb” with the actual filename of your .deb)
You may delete the .deb file after completing installation.
3. Did I forget to tell you, put the file you are installing into the /tmp folder on the iPhone/iPod. I like using Transmit for Mac for SFTPing files back-and-forth.