there is no simple way to do that and get great results, its a practice, rinse, repeat type of thing that you need to do over and over to really understand. Simplest way is have 2 layers, your base desgin as layer 1 and your color you want 'ripped' as layer 2. use marquee tool to get rid of the ripped portions then smooth over the edges with liquify and free transform>distort. after that it is a matter or burn/dodging your way to get the correct lighting and shadow as well as using downloaded textures and even more dodge/burn to get the texture of the ripped layer to look realistic. takes hours to do correctly, keep tryin.