It is easier to study harder if you know that a break lies just around the corner. Frequent short breaks reduce interference between different aspects of new information, thus allowing your brain to better store and consolidate the data. For these reasons, you should enact an intense 20-25 minute study session, followed by a 5-minute break. Use the five minutes to reward yourself by having a snack, taking a walk, calling a friend, or enjoying other positive activities. After every 3 such cycles, take a 15-minute break. Repeat this procedure until your study session comes to a close. Of course, actual study and break times may vary depending on your preferences. For example, if you believe you can retain more information by studying for 40-45 minutes with 10-minute breaks, then by all means do so. Just make sure you adjust your daily routine in a way that allows you to maintain these study cycles on a consistent basis.