RealStrat + Guitar Rig - Keyboard Improv

So I just got RealStrat and Guitar Rig to go with it. I totally don&know how to play rock/metal, as it&pretty obvious I&playing random notes. The main thing here is just testing whether the thing in fact sounds like a guitar (which is debatable, mainly because I¬ using any guitar techniques, i.e. hammer-on&etc.). If anybody has any advice on the faux guitar (like when to use hammer-on&please speak up. I know I&trying to play a guitar like it&a synth and that&a major issue, but I&working on it.