For your Sonic the Hedgehog party, focus on decorations like banners and balloons featuring Sonic, as well as tableware with Sonic designs. Hand out Sonic-themed favors such as stickers or mini figurines, and plan activities like an obstacle course or pin the tail on Sonic. Encourage guests to dress up as their favorite Sonic characters or provide Sonic hats for added fun. With these simple elements, you can create an exciting and memorable Sonic-themed celebration!