You only need to do this step if your card is not installed already. Before working inside your computer, be sure to ground yourself by touching the outside of the case.
Computers are very susceptible to damage from static electricity.
Find an open slot in your computer that matches the pins on the card. Remove the small metal plate covering the hole in the case behind the slot and firmly, but delicately put the card into the slot so the cable jack is towards the back of the computer where you just removed the small metal plate from. Make sure the card is seated firmly on the board and that you haven't accidentally dislodged any other cards or cables before putting the case back on the computer. Put your computer back together. Plug the provided blue cable into the back of your computer and into the blue jack on the wall.