Choose the color you want the outline to be and go to Edit and choose Stroke. From there you can set the width and whether you want it to be inside, outside, or centered. This is easier done in Freehand or Illustrator, but it can be achieved in Photoshop with the numeric transform function and the skew dialog. Remember older versions of Corel Draw may work much faster for you than the latest version, depending upon you application and needs. In a digital prepress work, flow many times a client wants a line art logo scanned and a little color added.
Most places scan it as line art-convert it to process and then color part of it.
Simply scan the work as line like always, then after converting and changing resolution, use color range to select blk. Now proceed coloring the rest of the logo or art and save. When making general tone corrections to an image, it'soften easier to use Adjust Variations than Adjusting curves manually. This works especially well when blending edges of dark and light or removing blotchy spots in skies or backgrounds after removing an object from them. Then go back to image mode and select greyscale, note there is no further change.