Struggling with my defense with my arsenal tactic

[Peteb66]

Heya
Started recently as Arsenal and In my opinion been playing some beautiful attacking possession football with my team. However as a tactical 'noob' I've been conceding a-lot of goals mainly due to poor defending and positioning. Tried to have a mess about with player roles specific instructions ect... but just not working, don't know where to start regarding roles and instructions. Just curious as to wether anyone can help me out with defending, however I want to retain as much of my formation as I can and midfield player roles, just want to focus on my back four mainly.
Thanks Peter
SS of tactic and instructions below |)

 

[Peteb66]

Anyone guys,Anyone?

 

[jassar]

Anyone guys,Anyone?

1) make ur defensive line 2 click less push up
2) make tempo 2 clicks fast
3) make playing style marking to default rather than all to zonal
4) set fullbacks at tight marking and run from deep rarely ,hold up ball to no
5) CD closing down own area

hope this will help and try to sign good defensive staff

 

[Peteb66]

Okay I shall implement it and see what happens, Cheers for the advice though