A party is a social gathering requiring three main elements: a reason, alcohol and prior invitation. What occurs when you have none of these requirements, but want to have a social gathering? You "Have People."(Technically most people would say "have people over" but ending with a dangling preposition is poor grammar, so "over" has been omitted in the interest of improving diction worldwide)
Having people is a spontaneous state of social gathering which often occurs in boring states like Wisconsin. To be a proper host/hostess the following things are conducive to creating a friendly and fun environment:
A very large, yet trashable and easy to clean-up room with comfortable furniture(basements are very effective), TV and blankets, pool and foozball tables nice extras if possible
A good selection of movies(Back to the Future Trilogy, The Star Wars Trilogy, Indiana Jones Trilogy, Kevin Smith movies, and Bond movies are must haves)
Soda, a fridge is a bonus
Board games and cards stashed in an non-obvious yet conspicuous place to be discovered by others "spontaneously"
Friends with DJing ability incase having people turns into a dance party
Friends like Mitchevious who are willing to sacrifice their dignity to visit porn shops and return with latex fists and engage in wrestling in interest of livening up the gathering
Random bizarre things such as inflatable smileyfaces, handcuffs, wigs, and children's costumes to create conversation pieces
Good Luck!