EDIT: I completely forgot that from the EASFC store you can buy instant wins for seasons which will give you an extra three points. This should really help if you are struggling.
Co-op seasons method
The achievement is in the title, you just need to be promoted to the next division.
The easiest way to do so (and the most fun) is to play co-op seasons with a friend which will require you to get 13 points out of 30 to be promoted. So all this requires is 4 wins and a draw which isn't difficult at all.
- Choose a high rated team such as Real Madrid or Bayern Munich as they have very fast wingers which will get you past defenders more often than not
- I found that for four games in a row my group was matched up to Bayern Munich when playing as Real Madrid. The opponent will inevitably be using Neuer in goal. The easiest way to score past him will be to use a finesse shot (hold down RB + B) as he usually over compensates for the shot.
- Team work is key for winning and it is usually a good idea to pass to a team mate than go for glory in a 1 V 1 situation. Remember no one else will know who scored so who's counting whether you score or not.
- The achievement will unlock after you are promoted to the next league. You will still be able to win the league overall so you will either need to carry on to finish or enter a game and leave straight away for the remaining games.
- This achievement should be doable in under 2 hours if you are able to win the majority of your games.
Enjoy your easy 55 gamer score!