Get organised.
 
I am an organised person, believe me, its helpful =D Here are some tips
1) If you get homework, do it right away when you get home from school so then it is over and doe with and you can spend the rest of the day doing what you want =D
2) TIDY YOUR ROOM! it feels so much better then to be in a messy environment (See my tips on tiding your room)
3) Buy a calendar/diary, so you are never late for meeting friends.
4) Buy a thing, you know that thing that you put on the draining board to put all your plates and knifes and forks in? Well buy one of them for 99p or so, and arrange all of your
 make up into it.
5) Don't leave loose pieces of paper around, buy a ring binder for a small amount of money and just put it all in there.
6) If you have younger siblings then don't leave things laying around they will just grab it then loose it for you, how kind of them lol. Put them in drawers or on high shelves.