Creating a brick wall texture

I was trying to go for having some cracks in the brick. The first thing i did was i chose a darker color grey and then i used a hard round brush. I made the brush size as small as i could get it and then i made some lines down the cracks. I made sure to make the lines different so it would look more life like. I would make lines from left to right diagonally and then from right to left diagonnally. I would also make sure that the lines are a little crooked because i don't remember actually seeing straight cracks in a wall.