I have to agree with LTK – if you take a photo of such a drawing using any camera or a high quality scanning device, then no matter what, the result will be disastrous. I mean, you'd have to deal with a huge load of fixes, removing a countless amount of pixels around the lines you've drawn and furthermore, all those totally empty spaces (maybe converting the image's palette to monochrome would somehow help a bit?). You could omit that repetitive kind of work by simply taking a photo of it using even a crappy mobile phone around (you know, these ones that include an availability to just take a photo while not being able to record any video of that), then put it on a plain document in some graphics editor like Adobe Photoshop (or Adobe Illustrator, as Impo suggested) or Corel PaintShop Photo Pro X3, or even Adobe Flash (my personal choice for such tasks) and basically trace the lines you've drawn (and naturally, remove the real photo after passing all the lines). However, I assume your goal here is about to make a map look like it has been really drawn using a pen, not a paintbrush apparently.