Windows: Internet Sharing

http://windows.microsoft.com/en-US/windows7/Setting-up-a-wireless-network#section_4

1.Open Network and Sharing Center by clicking the Start button , and then clicking Control Panel. In the search box, type network, and then click Network and Sharing Center.

2. Click Set up a new connection or network.

3. Click Set up a new network, and then click Next.