My best advice to you is to go into the DA and ask people for 1 on 1 fights. I it really doesn't matter who it is.
This will do 2 things for you.
1. Your aiming will drastically improve. This is because you are constantly in a fight, always trying to take shots. There is no waiting around looking for guys to kill or people who will run away from you, you always have somebody right there you are trying to kill and take shots on. Great for practice.
2. You will gain knowledge and understanding of basic/moderate ACM. I would recommend fighting with a better known vet because they can show you simple maneuvers that will take your flying to a whole other level.
Do not be afraid to lose in 1 on 1 fights in the DA, it is only just practice and a way to learn and handle the way a plane flies.