photoshop pencil tool in pixel art is not smooth precise

okay so basically when i click onto the canvas with my pencil tool, it is not very precise, the only time the pixel will be lit up is when the mouse courser is directly over the pixel(with grid lines active) how do i make it so that if my pencil tool is over some pixel that it lights up(colors in) the pixel that i am pointing to even if my mouse courser is not predominantly over that one particular pixel