Instructions
Participate in any mode within "Monday Night Combat," whether offline or online, and acquire $15,000 of in-game currency. A strong performance --- lots of kills, assists, ring outs, healing teammates, repairing turrets --- in any of the available game modes will allow you to gain in-game currency much faster.
Select the "locker room" menu option from the main menu of "Monday Night Combat." From the "locker room," select the "custom class" menu option. Highlight the first custom class spot and purchase it with your $15,000 of in-game currency.
Select the "position" menu option and choose the assassin. Select the "endorsements" menu option to pick your three endorsements (gold, silver, bronze).
Choose "speed," for the gold endorsement. For the silver endorsement, choose "skill recovery." For the bronze endorsement, choose "juice." This loadout will make your assassin slightly faster (she's ridiculously speedy already), and it will allow your nimble skills and "juice" power-up to be used more quickly and more effectively.
Set your endorsements in a different way to achieve speedy results, as an alternative. For the gold endorsement, choose "juice." For the silver endorsement, choose "skill recovery." For the bronze endorsement, choose "speed." This loadout will only boost the assassin's physical speed by a small amount, but her usable skills will recover faster, and her "juice" power-up will be enhanced greatly. The "juice" power-up puts the assassin into a frenzied state, speeding her up considerably.