If you are interested in costume design, consider joining a theater organization, such as a school drama club or a community theater. School dance troupes or film classes also may offer opportunities to explore costume design.

Unbuttoned: The Art and Artists of Theatrical Costume Design, by Shura Pollatsek, is a useful resource for beginning or experienced costume designers. 

You can practice designing on your own by drawing original sketches or copying designs from television, films, or the stage. Practice sewing and altering costumes from sketches for yourself, friends, and family.

Costume designers generally work as freelancers. After they have been contracted to provide the costumes for a production, they read the script to learn about the theme, location, time period, character types, dialogue, and action. They meet with the director to discuss his or her feelings on the plot, characters, period and style, time frame for the production, and budget.

For a play, designers plan a rough costume plot, which is a list of costume changes by scene for each character. They thoroughly research the history and setting in which the play is set. They plan a preliminary color scheme and sketch the costumes, including details such as gloves, footwear, hose, purses, jewelry, canes, fans, bouquets, and other props. The costume designer or an assistant collects swatches of fabrics and samples of various accessories.

After completing the research, final color sketches are painted or drawn and mounted for presentation. Once the director approves the designs, the costume designer solicits bids from contractors, creates or rents costumes, and shops for fabrics and accessories. Measurements of all actors are taken. Designers work closely with drapers, sewers, hairstylists, and makeup artists in the costume shop. They supervise fittings and attend all dress rehearsals to make final adjustments and repairs.

Costume designers also work in films, television, and videos, aiming to provide the look that will highlight characters' personalities. Aside from working with actors, they may also design and create costumes for performers such as figure skaters, ballroom dance competitors, circus members, theme park characters, musicians, and others who routinely wear costumes as part of a show.