How to download iOS 7.0.2 to my iPhone 4s without a wifi connection?

My iPhone 4s will not pick up any wifi signals anymore. I have a download update for the iOS 7.0.2 on my phone but since I cant get a wifi connection it wont let me update it. What can I do?

You can't update without wifi but I think you can connect your phone into iTunes and download from there

You could do so via a data connection though I don't recommend it at all. Also you could try doing so through your computer via iTunes.