I hear this a lot, and I myself have also gone looking for it…
So without further ado, here is the script that will install kext files for you – be warned – you’ll need to know how to get the kext file in the first place, as well as the filename.
Let’s get started.
Open the Terminal application by going to Applications / Utilities / Terminal.app – you will see it in the Utilities folder – it looks like a command prompt.
Once terminal has launched, type in the following command:
Enter the root or first user password that you inputted during the setup process.
This tells it to run any other commands after this one as the root or superuser account, allowing you to edit files you normally would not have permission to edit.
Here’s an example using IOATAFamily.kext, a popular ATA driver. You’ll want to replace this by your own driver name. Also, you’ll want to make sure the file is unzipped, and sitting on your desktop. Oh one more thing, you’ll want to edit YOURUSERNAME with… your username
mv /Users/(YOUR USERNAME)/Desktop/IOATAFamily.kext /System/Library/Extensions
chmod -R 755 /System/Library/Extensions/IOATAFamily.kext
sudo chown -R root:wheel /System/Library/Extensions/IOATAFamily.kext
rm -rf Extensions.mkext
rm -rf Extensions.kextcache
Hope that helps!