Pertama-tama share koneksi nya terlebih dahulu :

Go to Network Connections in your Control Panel by going to Start > Control Panel > Network and Internet > Network and Sharing Center and then click “Change adapter settings” on the menu on the left.
Right-click your Internet connection that you want to share (e.g., Local Area Connection) and click Properties.
Click the Sharing tab.
Check the “Allow other network users to connect through this computer’s Internet connection” option. (Note: for the sharing tab to show up, you will need to have two types of network connections: one for your Internet connection and another that the client computers can connect to, such as a wireless adapter.)
Optional: If you want other network users to be able to control or disable the Internet connection, select that option.
You can also optionally allow other network users to use services running on your network, such as mail servers or web servers, under the Settings option.
Once ICS is enabled, you can Set Up an Ad Hoc Wireless Network or use newer Wi-Fi Direct technology so the other devices can connect directly to your host computer for Internet access.

Kedua : create Ad-hoc Connection
Here’s How:

Go to Start > then right-click on Network and select Properties (on Windows Vista/7, go to your Network and Sharing Center under Start > Control Panel > Network and Internet).
Click on the “Set up a connection or network” option.
Select “Set up a wireless ad-hoc network” (Vista/7 have this as “Set up a new network”). Click Next.
Choose a name for your ad hoc network, enable encryption, and check the box to save the network. Your wireless network will then be created and your wireless adapter will start broadcasting.
On the client computers, you should be able to locate the new network and connect to it (for more help, see How to Set Up a Wi-Fi Connection

Tips:

Note the limitations of ad hoc wireless networking, including WEP-only security, the computers needing to be within 100 meters, etc. See Ad hoc wireless networks overview
If the host computer disconnects from the network, allother users will be disconnected and the ad hoc network deleted.
To share a single Internet connection on the ad hoc network, see Internet Connection Sharing