Attributes going down

My players' attrbibutes is always going down. Always! How can I get them to go up instead of down?

Do you set practices? Are they happy with their role and playing time? Some players expect to be given a bigger role, and some want more playing time, otherwise their morale will drop and their ratings will drop also. Some players you just can't satisfy, becuase you would have to make a trade or give someone else a lesse role, and then that players morale would drop, too. Scheduling practices through the coaching menu can give your players temporary boosts in their ratings, but scheduling too many can cause fatigue, which will lower their in-game performance.