A tip you sa? Okay.
Learn your class and learn other classes too this will help a lot, don't just stick with one class, also try to go as diffrent specs healer/DPS/tank. will inprove your knowlage as well as your game play. Make sure to know you playstyle before going into more dedicated things such as arenas it will make it easier for you to communicate with your partner. Also try ti find the misstakes you did and learn from them.
Good Luck!