The general way I try to learn is by having fresh ground coffee and doing the learning as early as possible in the morning after a good night sleep. It is also important to be motivated. No matter how much energy you have if you do not have desire and will to learn Physics and the Talmud and Musar then nothing can help. You need to have the will. But if that essential ingredient is there, then you need coffee. Fresh ground in the store. You do not need to cook it. You can mix it with water and and egg and drink it with Russian Halvah.
You also need a good night sleep before hand and as much as possible to guard that first hour when you wake up that it should be for learning alone. Nothing else.