usr13

To set up Network Address Translation (NAT) on a gateway machine, so that other machines on your network can access the Internet through it. You can use the following rule to do this:

sudo iptables -t nat -A POSTROUTING -o wlan0 -j MASQUERADE

You will also need to enable IP forwarding. You can do this temporarily, using the following command:

sudo echo 1 > /proc/sys/net/ipv4/ip_forward

Then set up your inside NIC

Set it to a static IP address like so:

sudo ifconfig eth0 192.168.3.1

At that point, (if you don't care to set up  dhcp server and caching nameserver):

Connect the client machine and set it's IP, something like:  192.168.3.2
Make it's default rout   192.168.3.1
Give it nameservers (as provided by your ISP, or just use 4.2.2.2)