No matter what color you want to print you need a positive for your screen that's completly solid black. When we go to expose the screen, the black areas block out the light to burn the image into the screen. Light rays go through the white areas of the paper easily but black blocks out the light. My drawing happens to be in black and I'm printing with black ink. I uploaded a scan of my image into the computer just to get the solid color as even as possible with a laser printer. I also cut out the area where there was some extra markings. If you have the means to print on an image transparency,
do that!