Q: Need to back up with no wifi

My wifi on iphone 4s has stopped working the button is greyed out, and the bluetooth won't connect to my IPAD. I have booked an appointment with the Genius desk for friday, so I need to back up my iphone through Icloud but it says you need a wifi connection big problem as this won't work on my phone.

Anyone know a way around this? as i don't want to lose all my photos and information held on my phone.

Thanks in advance.