Instructions
Select the Shipment map for multiplayer and before the game begins return to the "Barracks" in the main menu.
Select "Clan Tag" and enter "@@@@." An error box comes up, skip the box and begin the match.
Run to the corner where a brick wall and chain link fence meet and a tent is visible over the wall. There are two places on the map where the pair of crates aren't parallel as the outer is angled toward the other. Run to the left side of these, where the outer crate is at a steeper angle than the other angled pair. The dumpster is located in the corner facing the closed side of the crates, where they angle together like an arrow. Jump onto the dumpster in this corner.
Jump up again, while on the crate, and press the back button while in midair. The game goes to an error screen.
Have the host of the game fire at you until the clip runs out and use the knife on you 15 times. Press the back button after the host has finished with this. Your character will be launched into the sky.
Angle the fall into the direction of the truck beyond the wall. Land there and run wherever you please outside of the map.