To talk on this matter firstly I will say this"Confussion only occours when there are more than one way and you can't decide which way to choose.
Arrows confussion solved!
Arrows are just extra role assigned to a player.The player will play normaly just he will be given paticular task eg,to support more on defense or attack.Normaly he will play his position.
Red arrow gives freedom to player to play advanced attacking.
Blue arrows order a player to be in last line of defense and during opponent possesion the player will come back to defense immediately.
I also strongly recommend to avoid using much arrows.
Formation switching counfussion!
Counter formation are best against weak defense.Weak defense can be by quality or by numbers or even playing mentality(attacking).
If you keep on changing formations you will face difficulty in understanding your strenght.Only change formation according to situations.