Here are some random ideas from the web

1920s Maids and Butlers

Instead of flapper costumes or the 20s gangster costume, you can dress as the maid or butler of a fashionable house.

Your maid roaring 20s costume will probably include a long white checkered cotton apron, possibly with flower designs. Add a basic black top and white cap from all the classic movies of the 1920s and 1930s.

1920s Bathing Suits

Skip the 20s gangster costume. Even a gangster has to have a day at the beach. Likewise, leave the flapper costumes at home. Even the daring cigarette-holder-toting ankle-exposing women wore bathing suits that covered most of the body. 1920s costumes for the beach featured horizontal stripes, usually white and another color. Both men and women can wear these roaring twenties costumes. In a room full of flappers and zoot suits, your “day at the beach” roaring 20s costume will stand out.

Gangster Costumes

For 1920s costume ideas, men can dress in gangster costumes in fancy gangster suits, complete with costume accessories like vinyl spats, a fake cigarette puff, a gangster tie, a shoulder holster, a pocket watch, a gangster primafelt hat, a Tommy 10 gun, a dollar sign necklace and a zoot suit chain.

Flapper Costumes

For 1920s costume ideas, women may dress in flapper costumes, gangster molls or a Charleston queen, adorning herself with costume accessories like a flapper headband, a feather boa, an expanding cigarette holder, armbands, long white gloves, garters, oriental fans, fish net tights and a feather fan.

1920s Flapper Dresses

People often mistakenly assume that all dresses day and evening were short in every year of the twenties and that 1920s flapper costumes were the only fashion style of the twenties. Dress and coat lengths were actually calf length and quite long for most of the decade. Shortness is a popular misconception reinforced by the availability of moving film of the Charleston dance which shows very visible knees and legs on the dancing flappers.

Skirts only revealed the knee briefly between 1926 and 1928, and this was the only period when evening dresses were short in line with day dress lengths. This was the flapper period.

Roaring Twenties Showgirls

Get the man in your life to dress in a 1920s gangster costume, but beware...his Zoot suit buttons will pop when he sees you in your 1920s showgirl apparel. As flashy as flapper costumes, 1920s showgirl finery can look as exotic as the 1920s costumes in the risqué Casino de Paris revue with lots of feathers and barely-there lingerie, not to mention tons of jewelry and, of course, high heels.

You'll probably choose an outfit similar to the white sequined roaring twenties costumes Catherine Zeta-Jones and Renee Zellweger wear at the end of “Chicago.” A Parisian showgirl roaring 20s costume just might be too hot for your 20s gangster to handle!

Your Own 1920s Garb From Your Closet

You decided last minute to go with the 1920s theme for your costume party, but waiting until the last minute causes one problem: you don't have a costume. Don't worry - it's likely you have everything you need in your closet.

Flappers
Any one-colored knee-length dress with thin straps will do. Avoid the patterns and go for simplicity - the key is to accessorize. After you have your dress, find a pair of shoes with a heel with a round toe. Remember, Jimmy Choo didn't make shoes in the 1920s, so your favorite stiletto heels might not make the cut. But like most women, you probably have a pair of black pumps tucked away in your closet. Next, head to the jewelry box and think "pearls." If you have a long pearl necklace that's great, but if not, combine a few necklaces of different lengths together. For makeup, dark eyeliner and lipstick was in fashion.

Gangsters
You might have just worn it to the office for the boardroom meeting, but your suit can double as a gangster outfit. The most important accessory for this costume is the hat, so if you don't have a hat that will work, consult your friends and family for a loan.

Roaring Twenties Fashion

Part of the 1920s costumes included that women wore cloche costume hats. A cloche hat told everyone that you had short hair. It was only possible to get a close fitting cloche on the skull if the hair was cropped short and flat. The cloche hat affected body posture as it was pulled well over the eyes which meant young women held their heads at a specific angle in order to see where they were going. Foreheads were unfashionable in the 1920s

Flapper Costumes

Fashion statements for Flapper costumes:

• Dress: Low-waisted, sleeveless dress, called a "shift"
• Hemline: just above or below the knee
• Long fringe: on dress, purse
• Shoes: heels in black satin, T-strap or Mary Jane styles
• Makeup: outrageous eye liner and red lipstick
• Makeup extra: gold compact for powder
• Hair: short bob, either slicked down or curly
• Hat: cloche pulled down tight over short hair
• Silhouette: flat chest, boyish figure
• Boa: any color
• Beads: extra-long "pearls"
• Ultra cool: long cigarette filter
• Purse: black-fringed with long strap

Flapper costumes include straight, low-waisted dress just above or below the knee, long fringe on dress and black purse, black T-strap heels, eye liner and red lipstick, and a cloche hat pulled down tight over a bob haircut. Don't forget the boa, powder compact, long "pearls," and ultra-cool long cigarette holder.

Gangster Moll Roaring 20s Costume

Flapper costumes aren't the only 20s costumes available for women. Don your fedora and go as a female gangster! Wear hip-hugger Zoot suit pants and a double-breasted jacket. You're dressed to kill with a gangster tie on the outside, thigh-high stockings and a garter belt underneath. For a seductive showgirl twist on the traditional 1920s costumes, try a midriff-baring cropped top and miniskirt with thigh-highs and stiletto heels.

Fashion History in the 1920s

The roaring twenties saw a universal fashion for short hair a more radical move beyond the curtain styles of the war era. Hair was first bobbed, then shingled, then Eton cropped in 1926-1927. An Eton crop was considered daring and shocked some older citizens, since hair had always been thought a woman´s crowning glory. Only maiden aunts and elderly dowagers avoided the severe shorter styles, but by the 1930s softer waved hairstyles were a refreshing change.

Conversation Starters

Need some good conversation starters at your 1920s costume party. Take the lead with some of our fun facts from history:

• The "Great Gatsby" was written by F. Scott Fitzgerald.
  
• The end of World War I (1914-1919) brought in a new era of prosperity and giddiness.
  
• The booming stock market came to a crash in 1929.
• Women started wearing nylons
  # Alcohol Prohibition ushered in the illegal alcohol trade.
  
• Gangsters and organized crime protected the illegal booze business
  
• The 1920s brought in the Jazz Age.
  
• The Charleston was the dance of choice.
  
• Women were called Flappers because they were like baby birds just getting started.
  
• Flappers were also called Garconnes, French for "boys," because of the boyish fashion silhouette.