Managing time is a key to successful academic life. As an option, make a planning list in advance! If you are not experienced in list making, try to plan your next day only, beginning from morning till the end of your day. Try to highlight the most important things in your list in order to know the prioritized things.
Try to settle every single thing ON TIME! If you delay once, there is no surety that you will not do it again. As wisdom by Dale Carnegie, “Plan your day to achieve your goals. Keep to your plan!,” -Dale Carnegie-