did you install the calipers in there correct side cause the bleeder screw must be at the top not at the bottom cause if it is at teh bottom you'll never get any pressure cause there will always be air traped
you will need a friend to help you so he can pump the pedal till it gets hard to push down ussually about 3-7 pumps. Then you open the bleeder screw at the caliper you are at and let the fluid go out once you see very little pressure close the screw and repeat on all other calipers