How do you read a long text on a mobile phone?

I have never had a mobile phone before, and I don't have any instructions. I have a text, but it is longer than three lines and I don't know how to scroll down to read the end of it. The phone is Sony Ericsson (about 4-5 years old) and uses vodaphone pay as you go. Can anyone help?|||Is there a larger button on the control part?(see link)the one you probably pressed to read the message.just press the bottom of this to scroll down,the right to navigate right,left to navigate left ect.|||There should be a down button just under the screen