Get in the habit of looking at the oil in the pan. As it approaches the smoke point, its refractive index will change and its viscosity will decrease, giving a dimpled appearance. This is due to convection cells from the heating; it's easier to see in olive oil because it's relatively thick and dark compared to other liquids or light oils. In a round, level pan, you'll get a pleasing hexagonal pattern. Once you have nice stable convection cells you're ready to cook.
After a while you'll get used to your individual pans and how they transfer heat, to the point that you don't need to think about how to adjust the heat any more. Likewise watching the food itself will eventually tell you most of what you need to know about when it's done.