How to set up a Wireless Router?

[Girl Next To You]

Okay so I have a wireless router. It's a Linksys Wireless Router WRVS4400N and my dad has had some trouble setting it up. We got it a while ago, but haven't been able to set it up. I am really annoyed because alot of the homework I do involves the net, and when I am trying to use it in my bedroom the dial up cable won't reach. I have asked my dad to set it up, but he says there's a problem with it. I kinda need to know how to set it up because my dad's away and my mum knows nothing about things like this. I dont know where the instruction booklet is and I am really annoyed because wireless is easier to use.
PLEASE HELPPPPPPPPPPPPPP!!!!!!!!!!!!!!!!!!!!!!!