Place your green luggage next to the United counter and follow the red arrows until you reach the gate, before your plane departs. Feel free to push people and obstacles that get in your way :) .

Use [W], [A], [S], [D] to move, the mouse to look around and [Spacebar] to politely say "excuse me" -- although being polite at the airport won't make a difference in the game (or real life)