If your car uses a fuel rail to deliver fuel to the injectors, you removed it in the previous step. If you don't have a fuel rail, you'll need to remove a fuel line from the top of each injector. It's just as easy to remove, just do it carefully.
With the fuel delivery out of the way, you're ready to disconnect the fuel injectors. Each injector will have a plug at the top (or on the side near the top) that connects to the wiring harness. Most fuel injector wiring plugs are held securely in place by a springy wire (see pic). To remove this wire, just insert a flat head screwdriver in the space between the spring and the plug and pry it carefully away. It will come out easily. Don't lose it!