Router NAT settings: STRICT, I need to get it opened.?

My NAT is Strict, I need to make it an open or at least moderate NAT. The router is a Thomson TG782. I don't know how to enable uPnP or whatever and I need to do something fast. I can't connect with my friends on XBOX Live because the NAT is strict, a little help or a lot, whatever you have is great. I don't know router address to this router and I don't know what to do. HELP!