Use the Words
Every song tells a story, otherwise why write the song? When an artist writes a song, they are writing it in order to communicate a feeling or idea; in musical theater of course, that song must fit into a larger story and further the plot, but even pop songs are designed to communicate. Many people focus on pitches and pitches alone -they want to sound good (naturally), but sometimes that leaves the story neglected.
Most composers choose their lyrics very carefully. They select words which will best communicate the idea, the story, they are trying to tell. It does no good to gloss over these lyric choices. Next time you learn a new song, try reading the lyrics alone, without the music. This can help discern important syntax you might otherwise miss. For example, in the song Wanting from Rags the composer writes “…then I see his eyes and they dance, all they hold are lies, but they dance…” In this example, the word “dance” is chosen instead of the million other choices that could work - move, light, swing, swim, etc. - this can’t be ignored. The word dance connotes movement, levity, happiness, warmth, and much more, which is then juxtaposed with the lies referenced in the next line. This is all done deliberately to further the story and communicate to the audience how much pain this character is in loving a man who treats her poorly and she cannot have. This is just one instance in which truly analyzing the lyrics aids in the delivery of a piece.
In lieu of “performing,” trust that the words you are singing carry weight and meaning; trust the audience to understand and simply tell the story. Often, analyzing and paying close attention to the words you are given will help you find musicality in a piece you were otherwise struggling with. Of course gestures and movement can aid in your story-telling, but I encourage you to try every song standing still first. There is a power in stillness that most people do not utilize. After trying the song from stillness, you might just find more meaning in the words and the movements and gestures you then implement will carry more motivation.
Trust the words. Trust yourself to tell the story. Trust the audience to understand.