I tried diffusing several times, but unfortunantly, I never got the hang of it. I would check the piece you're talking about that came with your blowdryer because I know most blowdryers come with a concentrator attachment which does the opposite, it concentrates the airflow to a smaller section of hair. I just want to be sure you get the effect you're going for. Good luck!
Dense kinky-curly; healthy and growing strong!