This is a very easy achievement to get, and you'll actually unlock the 'Grindin' Solos' achievement along with it.
Head into 'Ultimate Team', accessible under the 'Play' tab. Skip past all of the steps by pressing whatever button you're prompted with, until you reach the 'Play Game' step. Complete this game by scoring (touchdown or field goal). Defend any plays by your opponent's team, should they get the ball back.
When you complete the game, skip past a couple more screens by opening some packs. After this you'll receive the 'Grindin' Solos' achievement and then the 'This Is My Ultimate Team' achievement.
Happy hunting!