Visit OWC's site and click the Tech Support link at the bottom of the page, you will then find how-to links one is for installing RAM into your machine. You can also consult your manual for instructions or any number of YouTube videos. Installing RAM in an iMac is incredibly simple (10 minutes max) just ensure the new RAM is firmly seated. Push it in with a very firm push using both thumbs until you feel it click in then press a little more to see that it won't go any further. Don't worry you won't hurt the machine. Pay attention to how the old RAM came out so you recognize the orientation the RAM goes in.