Getting a planner is probably one of the most important things you can have to keep organized during the school year. There are many different types of planners you can get. I like the Lilly Pulitzer called Trippin And Sippin in the large size. I personally love the colors (my fav colors are blue, green, and purple) and the large size is perfect if you're OCD like me.
The best thing about this planner is that you can plan on a monthly view and a weekly view. One of the things that definitely helps me is color coding. Okay, I know this seems totally nerdy of me but it seriously helps. I use a different color for each class that I take. I also have a color for birthdays/holidays and a color for activities like football games (tailgates) and club meetings. Writing what I have due on each day helps me manage my time and organize what I have to do each day.
A good thing about the Lilly Pulitzer agendas is that there are tabs for everything. I wrote my class schedules and what color goes with each class in the notes tab. This is great for random things that you might need throughout the semesters. If you're like me and forget when holidays are then the holidays tab is perfect for you (and me)! I also like how each month has a separate tab. So the first page of each month is a monthly view. The next few pages are each week in that month. I like to use both spots to write what I have due. On the monthly view page I write the general jist of what is happening. Then on the weekly view pages I write more details about the activity or class assignments.
The final tip is sticky notes. I cannot stress this enough how important this is. I like to buy the large sticky notes with lines on it. These are great for to do lists for the week and to put directly on that week. I also use the smaller sticky note pads in case I fill up a page in my agenda. The sticky note tabs are also great for marking off chapters in books.