For testing purposes I wanted to create a local network at home and found the solution here.
Too make it short:
1. Click Start, Control Panel, Network and Sharing Center .
2. Click Set up a connection or network.
3. Click Set up a wireless ad hoc (computer-to-computer) network, and then click Next.
4. Enter a name for your network, choose a security type (WEP is probably fine, given that you’re sharing your network with people you know), and then enter a security key.
5. Check the Save this network box, then click Next.
6. If you see a box marked Turn on Internet Connection Sharing, go ahead and click it.