Internet Sharing by Using Windows 8.1

Internet sharing can be enabled in Windows 8.1 easily, so that you can connect your other network devices such as computer, laptop, tablet or other mobile devices to Internet via this Windows computer.
This sharing feature is called Internet Connection Sharing (ICS), and the computer which you have enabled this feature is called ICS host computer. The main benefit of using this sharing feature is that you don’t need a hardware router to share Internet connection, but the drawback is that this ICS host computer needs to be on whenever you need to share Internet connection.

1) As a start, click Desktop tile on Start screen in order to go to Windows desktop environment that you are familiar with.
Windows 8.1 start screen
2) Next, right click the network icon on lower right corner of task bar area and click on Open Network and Sharing Center.
Windows 8.1 Network and Sharing Center
3) Once Network and Sharing Center appears, continue to click Change adapter settings.
Change wired and wireless adapter settings

Note: The other way is to right click the Window button and click on Network Connections.
Windows 8.1 network connections
4) Ok, if there are wireless and wired adapters installed on your computer, you will be shown a list of network connections that includes your wireless (Wi-Fi) and wired (Ethernet) connections. Right click the connection you would like to share Internet connection, and click on Properties. In this case, I right click my Wi-Fi connection and click on Properties.

Note: Please make sure you enable Internet sharing feature on the network adapter that connects to Internet.
WiFi adapter properties
5) Go ahead to click on the Sharing tab in network adapter properties, and tick the check box for Allow other network users to connect through this computer’s Internet connection.

Note: If you want other network users to enable or disable the shared Internet connection, tick the Allow other network users to control or disable the shared Internet connection check box. However I don’t recommend to tick this check box as this is better to be centrally managed by system administrator of this computer.

Note: If you have web, mail, FTP or other servers in your home network, you can actually click Settings… to select and allow the server to be accessed by Internet user.
Internet sharing in Windows 8.1
6) Proceed to click on Networking tab, you should un-tick Client for Microsoft Networks and File and Printer Sharing for Microsoft Networks check boxes, so that to better secure the network and won’t accidentally expose your home network resources to Internet. Firewall is also highly encouraged to be enabled on this ICS host computer. Click OK at last.
No file sharing in Windows 8.1
7) Later you will find out that network adapter will be shown with Shared wording.
Shared Internet settings on wireless adapter
8) After enabling the Internet connection sharing feature, the other network card connected to the home or other network would be assigned a static IP address with netmask (It would be the wired network adapter in this case). This ICS host will act as a DHCP server and assign other IP addresses in the 192.168.137.x/24 range to other client computers.

9) In order to access Internet, other client computers (Windows 8, 7, Vista, XP, 2000, etc) should configure TCP/IP on their local area connection to obtain an IP address automatically. Then those computers will be assigned IP address in the 192.168.137.x range and able to access Internet through this ICS host computer.
Get IP address from DHCL server
Related Readings:

Internet Connection Sharing (ICS) in Microsoft Windows
How to Connect Two Computers Wireless in Windows 7