Things You'll Need
Instructions
Pop out the cover of the expansion bay in the back of your PS2. Sony advises you to keep it closed until you have a Network Adapter so no dust enters the system. The cover should pop right off, without any requirement of a screwdriver.
Line up the Network Adapter's PCMCIA (Personal Computer Memory Card International Association) section with the input for it in the expansion bay. This should snap into place with ease, so don't force it. If it's not fitting, take your time to line up the corresponding parts of the system and the adapter, and try again.
Tighten the two screws on the sides of the Network Adapter. The screws are big enough to use a small coin to screw in, but a knife or a screwdriver will work, too. Avoid over-tightening them; if you break or strip the screws, they may not hold the adapter in place as well as they should.
Remove the covered tape from the cable inputs on the adapter. Plug in your cable into its corresponding input. Ethernet cables go into the bigger jack, while dial-up cables go into the tinier phone jack. Make sure these cables are plugged into a source of internet (router or phone jack in the wall). Turn your PS2 on and insert the disc that came with the Network Adapter. Follow the instructions to set up your online account with your PlayStation 2.