In honor of our most famous house elf Dobby, hold a contest for the Oddest Sock!
Advertise the contest beforehand on posters or invitations.
Challenge guests to show up with their "Oddest" Socks.
The contest judging can be a panel of judges or have all guests vote by specific criteria.
Hold a "Sock Parade" for all the contestants.
Offer prizes for different categories such as:
Most mis-matched pair
Most revolting color combination
Worst fit
Greatest number on each foot
Smelliest
Most Dobbyesque
and the closest match to Uncle Vernon's old yellow ones.