You will need to open your browser such as IE 6 and type in your modem address, then a log-in screen will appear for you to insert your username and password.
Please don't give your username and address here in the forum, but if you post back with the name of your ISP then Diodorus Siculus or one of the other forum members may be able to tell you what to type in to the address bar.
You need a cable/dsl broadband router for use with NTL cable BB. If its an ADSL router it wont work. You will also need the MAC address of the router (A unique 12 character address). and your NTL username which is usually your email address without the @ntlworld.com bit. See robin walkers website for some info click here I use the Linksys wired BEFSR41 wired 4 port router with switch to connect my PC's. This is a "plug-n-play" router and virtually needs little set up. Doesn't seem like much of a bargain if you have an unknown router with no instructions.
The MAC address you currently have registered with NTL will be the 12 character address on the back of your standalone cable modem which is connected directly to the NTL cable outlet. Your main PC ethernet outlet will be plugged into this standalone modem. If you have a modem as part of the NTL Digital box then I have no idea where the Mac address is listed.