How do I use match preparation?

This feature is bothering me alot, my first question when is the best time to use the special focus area, also if i choose defending positioning does it increase the positioning of all my players? what the hell is defending set pieces?:confused: is there a guide for this

I listen to what my scout says about the next opponent and also i bear in mind the opposition and whether im playing home or away.

So if its a league game and it says my opponents wont pose an aerial threat then i may prepare on attacking set pieces. If Im playing away and the team are good on the floor then its defensive movement. If Im playing a team in the cup thats in a higher league then defensive movement - unless i want to go for the jugular and it'l be attacking movement again.