You will eventually get suits in the game. You start out with your normal outfit which doesn't count as a suit for the achievement. To equip a suit once obtained, press and go to X-Genes & Suits. It should automatically be on suits. Press and highlight a suit and press .
Note: You can obtain this by using codes to get suits. You must enter these codes at the start menu. This at the very first screen you see. You will hear a confirmation noise.
Emma Frost Suit Hold and and press
Juggernaut Suit Hold and and press