Target Audience Research

To gain an insight on what my target audience do during their spare time, the places they shop and what they listen to; I have created a group on Facebook to ask questions to specific teenagers. I made the group and invited around 15 to 20 teenagers aged 16-18; I am going to be asking a question every few days on what I want to know about them, in order to gain the right audience group for my magazine. This is so that I know what to advertise/ what my audience look for in a magazine, as I don't want to apply something to my magazine that wont abode well with my primary audience.