1. wait for their Hogwarts letter, even once they've passed the age of 17.
2. have tried to speak to snakes in the zoo.
3. whisper words like "Pig Snout" or "Caput Draconis" when trying to open locked doors.
4. own and can tell over Tales of Beedle the Bard.
5. practice non-verbal spells in their head during boring classes.
6. point at things and mutter "Accio" while trying to retrieve them.
7. call people "filthy little Mudblood" when really trying to insult them.
8. will try to follow spiders if they ever see a trail of them.
9. have spent countless hours, walking back and forth down long stretches of hallways, muttering to themselves, trying to find the Room of Requirement.
10. have eaten countless jelly beans, hoping for an earwax-flavored one.