Make a Schedule & Follow it: The first step towards time management is to properly plan what you want to achieve in the given time period. You can make a schedule for a week, dividing the work daily into hours. Don’t just make a plan, follow it. Following the schedule can be difficult for you but it is absolutely essential to follow the plan that you make. This way no plans will be needed to get altered especially the academic ones.

Set Realistic Expectations: Don’t overburden yourself. Know what your capabilities are and your limits. Make a very realistic plan for yourself so that you don’t get overwhelmed. Typically you would not study more than 10-12 hours, so don’t create a schedule of 15 hours. You have to keep in account that you need time to relax, socialize and do other things, alas we all are humans and our brain function has certain limitations.

Eliminate Distractions: Isolate yourself from Mobile or other electronic devices that you use for entertainment. Switch off notifications from Instagram or Snapchat or any other social media you use. This way you won’t have the temptation to rush for your phone to see what notification you’ve received. Time is the highest wasted due to distractions, surround yourself with people who motivate you for good. 

Set Priorities: The crucial step where most of us go wrong; is deciding the priorities. Postpone unnecessary tasks. If you desire for a flexible time execution, perform activities in order of importance. Give ABC grading to tasks - "A" being the most important, this way by grading you will know what needs to be done at most urgency and what plans can be postponed.

Take Some Breaks: Did you know that breaks are as important as studying? Your brain has certain limits to which it can keep functioning. Typically teenagers can concentrate on a single thing for 10-20 minutes. It may vary from person to person, but you should give yourself rest for some time after such duration.

Make a "To-Do" List: Write EVERYTHING down that needs to get done. Organize by task list (school, personal, sports, etc.). Prioritize each task (see tip #4) and keep everything in one, centralized place.

Create a Routine: Your routine and expectations might not fit in nearly as perfect as you expected, and that is okay. The point is to make use of your productive times for the challenging tasks and your less productive times for the less challenging activities. Having a routine and sticking to it is incredible, but you should give yourself time. Productive habits take time to develop. If you are too hard on yourself, you might never have the chance of enjoying the benefits of a routine. Your success depends on how seriously you take your routine. The benefits outweigh the willpower you invest at every step, so it is worthwhile.