Again, scroll down and click on "Free." This opens a new page. Scroll down to a whole lot of text, but where you see some numbers telling you how many seconds you have to wait. They move.
Then, one they have gonepast the zero, the picture changes, and you see 3 coloured characters, slightly jumbled. These you have to copy into the little box provided. One you have done that, click on "Download," and all being well, it will begin.