When I first read the Little Red Book of Fly Fishing by Kirk Deeter and Charlie Myers, perhaps the tip that helped me the most was the idea that if you could see your thumb in your peripheral vision as you casted, you were casting within that old “10 and 2” range on the imaginary clock face.
I took the tip to heart, and it helped immediately. Here, Deeter describes and demonstrates the tip for you. Take my word for it. This will help your casting.