Draw a mustache on all of his self-portrait

Give him a cage of Cornish Pixies for his birthday

Give him a Mohawk

Through him a surprise party with all the people he memory-wiped

Challenge him to a Quidditch match with Harry

Constantly remind him that two twelve-year-olds beat him to the Chamber of Secrets

Sarcastically bow down at his feet whenever he enters a room

Whisper to your friends "That's the guy who erased his own memory" (loudly)

Hire Collin Creevey as his personal paparazzi

Repeatedly point out that he's no longer at the top of the best seller list

Say that even Kreature stole his Most-Charming-Smile award

Give his wand to pixies (by accident of course)

Tell him he needs to work on his signature

Loudly say how brave he was when he saved Ginny from the Chamber of Secrets. When he turns his back yell "NOT"

Ask him how he banished the Bandon Banshee. Then demand every detail you can think of (i.e. what color robes was he wearing or what style his hair was in)

Throw wads of paper at him just for the heck of him

Ask him why he didn't know what happened to Mrs. Norris

Play the Superman theme every time he's in earshot and shout "Save me!" in a high-pitched voice

Quote his sayings at him (fame is a fickle friend, Celebrity is as celebrity does)

Come up to him with a copy of Magical Me and ask him if he know what happened to the idiot that wrote it

Write horrible book reviews about his books in the Daily Prophet

Give him parental advice

Send him an anonymous note inviting him to a dueling lesson

When he bursts in ten minutes late put your arm around him and tell everyone "He has problems with his memory"

Burst out laughing in his classes for no reason

Burst out crying in his classes for no reason

Kick him in the shins and run away

Hum the pink panther theme and ask him where his wand is

When he tells you it's in his back pocket run and get Mad Eye

Replace his peacock quills with pigeon feathers

Conveniently leave Hermione's schedule with hearts around Lockheart's classes outlined in hearts in his classroom after Ron crossed out the hearts

Give him a Niffler for Christmas

Dye his hair red

Tell him he needs a set of false teath

Give him your dentist's number and say he does a great job with dentures

Ask him how to get rid of a Dementor

Have Moaning Myrtle haunt his office

Tell Dobby to knit a pair of socks for him

Cry when he doesn't wear them

Send this list to everybody in Hogwarts and St. Mongo's (For use)