Pace yourself by pressing [Back] to decrease your speed. There is no time limit. From time to time, return to get more points from flips.

If you keep falling backwards after attempting one of the vertical hills, try getting a good run up and holding [Left] to gain speed when going uphill. Then, hold [Right] at about one truck's length before the corner. If done correctly, you should go forward and make it over the hill.

When trying to go uphill, press [Up] + [Left]. This will give you a boost.