Maybe this is a really dumb problem, but I can never get my wingers or attacking midfielders to work back and defend which leaves just 7 at the back and 3 up the field, i play either 4-1-2-2-1 or 4-2-1-2-1, depends how defensive i need to be.
Wingers like Dirk Kuyt / Park Ji-Sung and generaly players with high work rate will always help the defense.
Also, read this : ''Aggression (to have the mental attitude needed to get involved), Bravery (to have the mental will to risk pain and injury), Determination (to have the mental desire to succeed in every action performed and scenario encountered) and Stamina (to retain a high work ethic for longer).''
Not that hard. Closing down to the max and man marking with tight mark on. But I won't put too much defending because I prefer them to stay forward so they can be ready for counter attack