Identifying a focus group

In order to identify a focus group consisting of my target audience, I posted a status on Facebook briefly explaining what I'm aiming to do and requesting males and females between the ages of 14 and 20 to take part. I decided to recruit on a social networking site because, typically, people of this age group are digitally literate and so check their news feeds regularly and are also probably more likely to offer their assistance if it's organised in an informal manner, as they are perhaps not as familiar and/or comfortable with a professional/serious environment as an older audience may be. With this in mind, once enough people have replied (ideally, I would like an equal number of males and females, and a range in ages), I will create a Facebook group for my focus group where we can attempt to organise meetings during which I can present my ideas/work to them and film their feedback OR I could simply link things from my blog and/or other websites onto the page and use the poll tool to collect feedback (or simply post questions).