This is a meme I found

1) Scream and shriek loudly and tell them you're speaking Mermish.
2) Always speak in a British accent (if you're not from the UK)
3) Relate everything they say to the Harry Potter books & movies.
4) Crowd their inbox with HP-related emails, and make sure the subject are misleading.
5) Give them Harry Potter merchandise for their birthday and demand they treasure it forever.
6) Pretend you can do magic.
7) Yell "Crucio!" or "Avada Kedavra!" if they insult Harry Potter.
8) If you're late for something, blame it on your broken Time Turner.
9) Sort every person you meet into one of the Hogwarts houses....