You may find it helpful to change your schedule to take advantage of times when you have more energy and feel less tired.
Keep a diary for a week or so, and record the times of day when you have energy and when you are tired.
If there is a pattern to how your energy levels change during the day, try to plan your work, school, or other activities around that pattern. If there are certain times of day when you are usually very tired, plan to rest at those times. When possible, plan work and other busy activities for times of day when you feel more energetic.
Resist the temptation to overdo it when you are feeling energetic. If you try to do too much, you may become overtired, and it may take several days for you to recover.
It is not always easy to adjust a busy schedule. Keep in mind that even small changes can make a difference in how tired you feel.