Just a reminder before I continue: You should have the PDANet drivers installed by this point; otherwise you’re on the cusp of frustration (I didn’t have them installed the first time I attempted this hack). You'll get some warnings about unverified drivers; this is fine, install the PDANet drivers anyway. You don’t need to run the application (it conflicts with adb); just install it.

You should have installed the Google USB Driver Package from inside the Android SDK application (it’s one of the main options), so you should be all set to plug the Nexus S into your computer. Nothing should happen on the PC, do not enable USB storage on the phone. Right click on My Computer and go into Manage, and then Device Manager. In your Other Devices section, you should see your Nexus S with a little yellow exclaimation point. Right click on it, and select Update Drivers, pointing to where you installed the USB drivers.

Here’s the old-school part: go into a command prompt by hitting the start button and typing “cmd” (no quotes) in the search field, then pressing return. This will put you in C:\users\yourusername in Windows 7. If you unzipped the Android SDK into C:\android, for example, now type “cd ../..” to put yourself into the C: base folder, and then type “cd android” to put yourself into the SDK folder. If you unzipped it/named it something else, just substitute it for the above.Type “adb devices” (no quotes) at the prompt and you should be greeted with a serial number. That’s a good sign. If you don’t see that, you’ve skipped a step somewhere.

At this point you can type “adb reboot bootloader” (no quotes) into the command prompt window and press Enter; your phone will then reset into fastboot mode. It should install the drivers automatically from your PDANet installation. If it says “waiting for device” the PDANet drivers were not successfully installed.

Now you can put in the good stuff: “fastboot oem unlock” (no quotes) into the command prompt, then press return. If you didn’t copy the contents of platform/tools into tools in the main folder, you’ll get a "command not found" message as I stated above. If you did, your phone will throw up a warning about unlocking and voiding warranties. Tap Yes on the phone, and your command prompt will echo OK, and tell you how many seconds it took you to decide to void your warranty (it took me something like 15.234 seconds). That’s it. You are now the proud parent of an unlocked Nexus S!