Using a "wizardly" font and Professor McGonnagall's first letter to Harry as an example, create a personalized invitation for everyone on the guest list. If the exact location of the person's room in their house is known, be sure to put it on the outside of the invitation!
Print the invitations in green ink, put them in envelopes and hand them out!
Hang several "haunted portraits" (which can be found seasonally at party supply stores).
Place cornstalks and pumpkins around, throw spider webs around the corn stalks and then stick little black spider rings into the spider web to create "Aragog's Nest", and hang a large cardboard spider above it.
Make an enchanted ceiling by purchasing a roll of navy blue table covering some glow-in-the-dark stars, silver glitter, and a package of 10 little pumpkin buckets. Measure how long the ceiling is, then simply cut the table covering to fit. Glue glitter and stars on to the table covering, hang it on the ceiling and hang the pumpkin buckets from it!
Mix your own potions using household supplies, food coloring, and small potions bottles (available at arts & crafts stores). Put raisins in one and called it frog brains, a couple of spiders in another, and some jelly slugs in another.
If more decorations are desired, simply hang some bats, pumpkins and skulls about!
Hide the "Game Den" behind Aragog's Nest.
Set up a video game system and television so that the guests can play Quidditch World Cup.
Have an area for playing charades.
Have separate areas for different Potter-themed board games. Harry Potter Scene It, Harry Potter Uno and Mystery at Hogwarts are a few choices.
Try Licorice Wands, Ravenclaws (A bag of Bugles placed in a plastic cauldron), Dirt Cake, Dragon Snot, Dragon Blood Punch, Apple Cider, and a big bowl of Bertie Bott's Every Flavor Beans to tempt the guests!
© Carla S.'s party ideas were taken with permission.