Firefox, see sticky guide.
Starhub users, I don't know what proxy Starhub is using.
Singnet users - type in proxy.singnet.com.sg Port number is
8080
Set proxy in Internet Explorer
1. Select Tools => Internet Options.
2. Select the Connections tab.
3. If you are using LAN, click the LAN Settings button.
If you are using Dial-up or Virtual Private Network connection,
select necessary connection and click the Settings button.
4. In the "Proxy Server" area, click the check box next to Use a
proxy server ....
5. Set Proxy Server address - proxy.singnet.com.sg, port -
8080.
6. Click OK
Set proxy in Opera
http://www.opera.com/support/search/view/332/