hm, what?
can you explain it a little better?
don't quite get the question

also do you think we could see what exactly it is you're scanning?

If you want to draw over your image in Photoshop... don't take a sharpie to the monitor for one thing.

In your layers palette there's a button at the corner that looks like a page with a bent corner. It's a New Layers button. Click that and you'll get a new transparent layer above your image. It's like a tracing paper... so you can draw on it but it won't affect your original image.

Then press B which is the brush tool, select what type of brush you want from the top and draw over it.

oooo...ty