Post Its!

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What is the most useful stationery item to help you be organized in your study routines?
Post its!

Get a huge stack of post its and use them everywhere! Use it as reminders, use it as calendars, use it for notes, use it for labeling, anything!
Post its help you keep things very organized and tidy, try using them if you haven't, and if you have, just start using them extensively and see the difference.