When they’re onstage, Lela Elam, Betsy Graver, Ethan Henry, Katherine Amadeo and Alex Alvarez aren’t themselves. They become other people, the characters in a play, and what they wear is what South Florida’s top costume designers create or choose for them.

But on Monday evening when actors, directors, designers and others gather at the Broward Center for the Performing Arts for the 37th annual Carbonell Awards — or “Theater Prom,” as the region’s top theater award ceremony has been dubbed by the artists it celebrates — these five nominated actors will be expressing the most glamorous versions of their own taste and style, as will the 33 other actors honored with nominations for their work in plays and musicals during 2012.

Elam, who won a best actress Carbonell for her performance in GableStage’s In the Continuum, is nominated for two more this year. In the Zoetic Stage world premiere of Michael McKeever’s Moscow, Elam wore a maid’s uniform (and earned a best supporting actress nod) as Olivia, a woman working for an affluent family in early ‘60s Miami. In Ruined at GableStage, she wore colorful African dresses (and got a best actress nomination) as Mama Nadi, the operator of a brothel in war-torn Congo.

But offstage? The fashion-conscious actress is all about rocking different looks and creating an impression.

“Honestly? I want everybody to look at me and be like, ‘Oh my God, girl, you look so good!,’ ” she says, laughing. “We work really hard and don’t make a lot of money. So at the Carbonells, I like to work it. It’s our prom.”

Elam currently favors green or blue nail polish, sparkly to match her personality. When she wakes up in the morning, she thinks about what kind of look will work for her day and her mood — hip-hop, professional lady, glamor girl — and puts it all together. It is, she says, “like you’re the costumer of your life.”

The princess-like white Jessica McClintock gown she wore to the 2008 Carbonells was a last-minute substitution. She had bought a corset-top, crystal-beaded black gown, but when she tried it on two days before the ceremony, she discovered it didn’t fit. More worrisome, her hand and foot were badly swollen. When she saw a doctor the day after the ceremony, he guessed she had lupus, and tests soon confirmed the diagnosis. Elam has been managing and living with the autoimmune disorder ever since. But on that special night, wearing the gown and wider shoes, she felt beautiful.

“I walked out wearing the gown, and my dad just gasped. He didn’t even do that for my real prom,” she says.

Graver and Amadeo are both competing with Elam (and with Harriet Oser and Laura Turnbull) for best actress in a play. Graver is nominated for playing Vanda, an auditioning actress, in David Ives’ erotically charged Venus in Fur at GableStage. Amadeo got her nomination for playing the frightened young governess in Naked Stage’s gothic thriller The Turn of the Screw at Barry University’s Pelican Theatre. Coincidentally (or maybe not), both actresses did their two-character shows opposite Matthew William Chizever, nominated as best actor in a musical for playing Henry Higgins in Stage Door Theatre’s My Fair Lady.