Every turnover is a thrower error.
You need to pass the disc to your teammates when THEY want you to, not when you want to.
If you are not actively pursuing a comprehensive strength and conditioning program, it is very likely that you are going to get injuried.
It is way better for the D to set up than for the O to set up.
The best way for a novice thrower to improve is for them to watch the body mechanics of great throwers and attempt to emulate what they see. Precise instruction does not work as way as careful and watchful plagiarism of total body form.
Thinking is bad. Allowing your body to do what it has been trained for is the way to unleash peak performance.
If you want to get a freshman out to practice, throw with them for 5 minutes and then give them the disc.
Drills lasting more than 10 minutes bore people.
Practices need to be hard.
If you forget why or how you love this sport so much, choose a practice or a tournament and try to be the very last person to leave the fields. Think for a bit about the way you feel out on that grass. Is that shop you are sitting on the same spot you got your last layout D?