Once you get use to the game's feel - best described as "dodgy" if you didn't catch the theme of the past paragraph - you're basically tasked with following the checkpoints on your mini map to trigger missions, which range in substance such as races, stealth missions, but often are puzzle based. As mentioned earlier, you are required to keep Oliver rested. You can rent hotel rooms and such throughout the game, which will fully restore his energy, but if you keep running around and deplete your energy, you will fall to sleep anywhere and wake up half energized, so at times it seems hardly worth the travel back to a hotel room just for full energy.