Select a topic that will interest your teen reader. To determine what topics teen girls are interested in, pay attention to other media aimed at them. Read teen magazines and contemporary teen fiction and watch popular teen TV programs to see what's buzzing around in the world of teen girls.
Plan a fast-moving plot. Contemporary teen readers often won't wait for a literary payoff. When planning your plot, don't spend too much time building your characters, setting and rising action. If you do, you may lose some of your readers who choose to tune out instead of waiting for your first action-packed moment.
Craft a realistic setting that allows readers to immerse themselves completely in the time and place. If you are writing a contemporary story, visit the setting you intend to write about. For example, if much of your plot takes place in a mall, go to your area mall and observe everything there. If your setting is in the past, research this time period to craft an accurate setting.
Include characters to which teen girls can relate. This does not mean that your characters need to be teen girls themselves, although that may certainly help. Ensure that your characters are ones teen readers will care about and, at least to some degree, identify with. For example, a female teen main character who struggles with feelings of insecurity could prove effective, as many teens have felt similarly and could relate to this protagonist. Alternatively, a main character who appears popular and put together but struggles with emotional challenges could also engage your readers and show them that things (and people) aren't always what they appear to be.
Create a natural, authentic voice for each of your characters. Teen readers will be able to tell immediately if you are not hip to their ways of speaking. If your characters are teens themselves, keep your ear tuned in to teen conversations. Integrate some of their slang into your dialog instead of using tired expressions from a bygone era that you may have used at their age.
Decide on a meaningful message underlying your tale that leaves your reader with some deeper understanding of herself or the world in which she lives. For example, compose a tale in which the protagonist is partnered for a school project with a handicapped individual to whom she had never previously paid attention and, upon working with this individual, comes to realize that she has made assumptions and doesn't always give people a fair chance.