I'm afraid you've bought the wrong thing
A switch is a device for expanding existing networks, such as in an office, but doesn't have the ability to share a home broadband.
What you need is a Cable Router. This looks like a single network connection as far as NTL/TW is concerned, but shares that single connection with the four internal ports (and/or wireless).
If you don't need wireless and you are on NTL/TW broadband, something like
this or
this is what you need.