How to make camera video time longer?

I have a new nikon dx af-s nikkor 18 55mm and i want to take videos but it is set at 1min and i can't find out how to change it please help?

It's most likely not set at one minute.

Did you format the memory card in the camera prior to shooting?

What's the speed of your card? You need a class 10 card, the fastest currently available.

Format in the camera before shooting anything, stills or video.

A "nikon dx af-s nikkor 18 55mm" is a lens, not a camera. You will have to tell us what the camera is in order for us to help you. Or, you could just read the manual.