A few advices when making tactics:
- I've seen some playing videos that say "I want this style" then tick every thing that there is that can go in that direction. This will make things go to the extremes and extremes rarely are good. In fact, it can get the opposite result to what is intended. Short passing and retain possession and lowest tempo and... may end with your team hoofing the ball immediately: because they've given such settings that when pressed they won't see beyond six yards and if no players are that close they'll just want to get rid of the ball. Let them not keep possession or tell them to make longer passes and then they'll look further for team mates and when under pressure they will look better for them and find them and in consequence keep the ball without hoofing it.
- Football Manager is realistic tactics, not an MMO. This links to the previous. It means you don't go saying "I will set what I have strong to the max and that I have weak dump it". That may not give your strong part so stronger but will leave your weaknesses exposed and in the end make you much weaker. You have to take advantage of your strengths, sure, but you have to work also in compensating or disguising your weaknesses.
- The answer is rarely the first thing that pops to mind before careful consideration of the problem. Taking again the example linked with the first point: if your team is losing the ball often and making too long passes, some times the answer is not to tell them to pass shorter, but let them to look for longer passes. If your team isn't breaking the opposition's defence, maybe going more offensive is not the answer, but more defensive: by going offensive you'll get the ball higher up the pitch with the opposition starting from better defensive positions, by being more defensive and letting them come to you, you can then make counter attacks where their players aren't well placed for defense at the beginning and your speed can actually get the ball up before their defence is organized.