For Wired Connection (Internet Cable connected to Computer)
1. Click on the Apple in the Upper Left Hand Corner of the Screen.
2. Click System Preferences.
3. Click Network.
4. Select Ethernet on left side of box.
5. Click Advanced in lewer right corner of box.
6. Click Hardware tab.
7. Mac Address should be in this format 00:00:00:00:00:00
For Wireless Connection
1. Repeat Steps 1 - 3 above
2. Select Wireless (or Airport) on left side of Box.
3. Repeat steps 5 - 7 above