How do you attract/address your audience?

listen to podcast-
http://www.humyo.com/10347999/addressing%20audience.mp3?a=irADR31pRdk

My target audience was created rather than aimed for, either way i achieved on attracting my audience by having certain conventions that allow them to be subject to influence e.g. race, the majority of my trailer is made up of Black cast this can lead to a majority of black audiences because social groups tend to follow there own kind for varies different reason like; culture and preferences. I aimed for a age range between 15-30 i believe I've achieved this by making the characters within the trailer 'students' that have just finished college and are heading to university and knowing that most university students graduate around the age of 22-24 i believe these ages will be able to relate to the style of which the students are portrayed e.g. having a night out/ having fun. The setting of all this is within a park in a urban town so urban people may also be attracted to this simply because they can relate to urban life and lifestyles. Posters aren't usually bought but seen so my strategic selling point would be to place them around fast food shops, around schools, colleges, universities, generally places where students will be able to see them easily and often so the more they see it the more they get influenced and the more they might want to watch it. My magazine is low priced so this can appeal to a lower social economic barrier, my main target audience is full time students many of them don't have a jobs so the price can be easier on them to acquire.