Go to control panel click on network connections then click on new connection wizard. Choose option "connect to internet", click next, then choose option "set up my connection manually, click next, then choose option "Connect using a dial up modem", click next, from the list of modems provided click on yours to select, click next, then choose a connection name (this can be anything you like), click next, then enter the connection number 147008451400101, click next, then enter your internet account information,click next, then click finish, job done.
The 1470 is to enable caller line identification (CLI) should the number you are using have it disabled. CLI can be disabled on a line, the effect is that when you phone someone on a land line with a caller identification display it would show "withheld". It would probably show something like "private number" on a mobile. PlusNet wont allow connections from withheld numbers.
I'm guessing you'll get a desk top icon, I can't remember off hand, but if you don't then go into Control Panel / Network Connections and you can click on it from there.