First you must obtain the Halo Topper if you have not already, just play online matches until you get it.
Once you have the Halo Topper, you should equip it, and set up an exhibition with the following settings:
Game Mode: Rumble/ Snow Day/ Soccar (up to you)
Arena: Starbase ARC
Difficulty: No Bots
Max Score: 1 Goal
Launch the game and when it loads, chose a team, score one goal, and Voila! Achievement unlocked!