Somebody e-mailed me wanting to know how it is to create a pattern that looks a lot like a coloring book using Photoshop. Actually there are lots of different ways to do it. But since I like to mix-up things, this is my favorite way!
Here are the steps:
Duplicate the layer of the photo that you have chosen.
Then go to menu FILTER>OTHER>HIGHPASS. You can set it to 13.9 radius. But I suggest that you choose the setting wherein the photo looks as if the edges have a halo like highlight around it. Experiment guys! So, you’ll know what setting works for you.

Go to menu
FILTER>STYLIZE>FIND EDGES. You will notice that your photo looks as if the edges have been colorized by different rainbow colors.

Next step is to change the color to black & white by going to
IMAGE>ADJUSTMENT>BLACK & WHITE

Now, I want to sharpen the edges more. I do this by going to
FILTER>SHARPEN>UNSHARP MASK. For this project I used 50% amount, 53.7 radius, & 0 threshold. But again, these settings are what worked for my photo. I am suggesting again that you play around with the sliders again to see what works for you. However, I suggest that you keep the threshold to zero (0) and then play around with the amount and radius to make the edges “pop-out”.

Now you’re done! If there are unwanted gray or black marks, just paint them using the brush and the white color!