I'm not too great at the game, I just like building teams and collecting shiny cards tbh.
My advice would be...
Turn off messages from non friends.
Be prepared to play against some utter arseholes, willing to do almost anything for a win.
The first 5 games can be a bit of a lottery imo. Don't be disheartened if you get hammered in a couple or lose them all. You'll find your level.
Tactically, have a plan b. Try not to be too predictable.
11 wins is a decent target to aim for at the start, and should be within reach of most people who play. This will get you automatic entry next time.