Windows users can change their IP address using the Windows Network and Sharing Center, while Mac users need to use System Preferences. Both these options allow users to enter the IP address they want to use.
On Windows Vista, the first step in changing the IP address is to open the Control Panel. From here, click on the Network and Internet icon and open the Network and Sharing Center. Next, click Manage Network Connections to bring up a list of network connections. A similar list can be accessed on Windows 7 by clicking View Network Connections in the Network and Sharing Center.
Right-click the connection that needs a new IP address, and then click the Networking tab. Select either Internet Protocol Version 4 or Internet Protocol Version 6, and click Properties to change the IP address for this type of connection. To obtain a new IP address automatically, click Obtain an IP Address Automatically or specify an IP address by clicking Use the Following IP Address and entering the IP address that the connection should use.
On a Mac, start by choosing System Preferences from the Apple menu, and then click Network. From the Configure menu, choose Manually, and enter an IP address in the relevant field.