Before we get into the specifics of throwing a roaring 20s party, kudos to you for choosing a truly unique and special era with which to celebrate. If all goes according to plan, your party will teach your friends and family the carefree nature of the roaring 20s!
Alcohol was illegal in the 20s, which meant that those who chose to drink did so in very particular, illicit settings. And, many drinks were invented during this time. Celebrate this by serving roaring 20s cocktails, such as Brandy Alexanders, Bees Knees, and Gin Fizzes. If you’re not sure how to make these cocktails, purchase a vintage cocktails recipe book. Distribute whatever spirits you’re offering into nondescript, unlabeled bottles, and put them on display.
The decade’s diverse social trends provide a wide variety of costume options. For example, guests wishing to represent the booming liquor-smuggling industry can dress up like Al Capone by wearing pinstripe suits, flashy ties, and crooked hats. On the opposite end of the spectrum, those wishing to represent the prohibition movement can dress up like farm folks. Women can adapt the “flapper” look by bobbing their hair, wearing loose dresses that fall just above the knees and expose the arms, wrapping long strings of loud pearls around their necks, and painting their nails in garish fashion. Likewise, men with a flair for music can take on the “jazz band” look by stalking around the party blowing trumpets (fake or otherwise) and wearing black suits, white shirts, and black bow-ties.
Decorate your house to look like an old-fashioned speakeasy. This means: Dim lights, wooden tables, dark curtains, a smoke machine (providing all the ambience of chain-smoking patrons without the risk of lung damage), and wary bartenders in coattails. Requiring a password at the door, which you can include on your invitation, will stay true to the roaring 20s speakeasy style.
Given that the 20s are often referred to as “The Jazz Age,” your playlist should contain a lot of jazz. The most popular musicians of the era include Bix Beiderbeck, Louie Armstrong, Duke Ellington, Fletcher Henderson, and Earl Hines. As it is unlikely that many of your guests have ever danced to this sort of music, print out a few guides to popular 20s steps, such as the Charleston and the Breakaway, and hang them on your walls.
Lastly, here's a fun game that you and your guests can play to make the party come full circle: A few days before the party, call a few of your most trusted friends and request that that they join your "liquor prevention committee" by arriving at your house dressed as policemen. On the night of the party, distribute stacks of fake money to the rest of your guests and explain that if a policeman sees any of them consuming alcohol, they will have to hand over the money as a bribe. Likewise, explain to your police force that if any of them are caught imbibing, they too will have to bribe their way out of the situation or risk losing their job. You could even promise a wonderful surprise to the person with the biggest billfold at the end of the evening!