To start, set up the very network equipment, usually a router. To do this, connect via LAN-port of your equipment with a network card. Then open any Internet browser and in the address bar enter the IP of your router (e.g. 192.168.1.1, read the manual of your equipment). After that will appear the login form, which you must enter username and password (most likely admin). Then, examining the interface page, find the WAN option and activate it.
Then go to "default gateway" (in English it may sound like a Server address). In the text field enter the desired value for the gateway. Here, if necessary, you can dig in the DNS servers settings, which are closely linked with the gateway. To do this, uncheck the checkbox next to "Obtain DNS automatically" and enter the required addresses. Save your changes by clicking on the button Save or Apply and then restart your network hardware to ensure that the settings took effect. It is also possible to configure the default gateway in the computer. To do this, click "start" and go to "control Panel". In the window that opens scroll to the "Network and Internet" and open it.
Then click on the object called the "Center network and sharing". In this section, select the option "Manage network connections", after the discovery of which immediately go to "Network connections". Right-click specify the adapter for which you want to configure a default gateway. Select "Properties" in the opened window go to the tab "Network". Under "Components used by this connection". Click "Internet Protocol version 6 (TCP/IPv6) or Internet Protocol version 4 (TCP/IPv4)". Select "Properties" and click on the option "Obtain an IP address automatically" or "Use the following IP address".