Dying My Hair. With Home Kit. EXTREME COLORS! Any advice?

Well, this weekend, I'm dying my hair. Black, purple undertone, and a black and bleached coon tail. My natural hair color is a light brown and i currently have a pink undertone which has faded throughout the months. The purple comes with the bleaching kit so it pops more, the black i am going to buy tomorrow. And the coon's tail seems pretty easy. All i want is some advice that anyone may have into making my dying procedure easier and more effective. Thank you. (: