How to Turn Your Photo Into A Sketch Quick and Dirty
(Or.....How to Make your Photo, Not a Photo)
by Daryl Moistner
Open your photograph in Adobe Photoshop and duplicate it into two additional layers so you have a background, and a Layer 1, and a Layer 2.
On Layer two click the blend box as indicated by the red arrow below and set it to Color Burn
Click on Layer 1 to make it active then create a Hue and Saturation adjustment layer by clicking on the circle as indicated by the red arrow below. When the hue and saturation box comes up push the saturation slider all the way left to -100.
Click back on Layer 1 then go to Image>Adjustments>Invert (or Control I on a PC). Then click on the blend mode and change that to Color Dodge. The image will turn mostly white.
And the last step is to go to Filters>Blur>Gaussian Blur, and when the Gaussian Filter box comes up move the slider left or right until you get the effect you desire.
You can see some more examples at my site on Photosig.