The single best piece of advice I ever got as a writer was when I took a fiction writing workshop in college and the professor, Dr. Markus, said, "Don't tell me, show me." Don't tell me the character is angry, show me that the character is angry. Don't tell me that the character lives in Detroit, show me that the character lives in Detroit.
Take a look at the following examples. Example 1 is something I lifted word-for-word from a student's draft, changing only the names of the characters. Example 2 is a suggestion of how the writer might show us what she told us in the first example. The texts have been color-coded to show some of the corresponding elements.
Deanna and Beverly are best friends. Deanna is an ordinary fifteen-year-old who is sure of herself and very independent. Beverly, on the other hand, is a fourteen-year-old who has a very low self-esteem. She has a boyfriend who is nineteen and knows he could get away with anything because Beverly lets him do whatever he wants to do.
"Oh, yeah!" Deanna exclaimed, standing before a full-length mirror with a smile as bright as her outfit, "I look good! This is definitely me. What do you think?"
Beverly looked up at her best friend and replied sheepishly, "Uh. . .yeah, I guess..." her voice trailing off as she looked down and began to fidget with some of the cosmetics on the vanity table, silently wishing she could look so ravishing in the same clothes.
Deanna twirled playfully before the mirror and laughed, then stopped as she noticed Beverly aimlessly twisting a lipstick in and out of its case. "Girl," she began, crossing the room to Beverly's chair, "will you get your mind off that boy for one minute? I mean it, he's too old for you."
"He is not," Beverly replied, looking away from Deanna. "He's only nineteen."
"Oh yeah? And you're fourteen!"
"So?" She shifted uncomfortably in her chair as Deanna stood over her with a stern expression on her face. "You're only a year older, you can't tell me what to do."
"Yeah, well you don't see me dating no nineteen-year-old! Jeez, have some respect for yourself! Bad enough you're dating this guy, but you just let him do whatever he wants! I tell you, girl, you better hold on to him. You keep this up, you don't keep tabs on him, you're going to lose him."
Note that most of the color-coded phrases in the second example have actions in them; one of the characters does something, while the first example is merely a series of conditions. In other words, Example 1 uses verbs-of-being, while Example 2 uses verbs-of-doing.
Whenever you write a story, every sentence should have an action in it somewhere. Try to use verbs-of-doing rather than verbs-of-being; if you have a verb-of-being in your sentence, make sure there's also a verb-of-doing in there somewhere.