First you need to create a 5 pixel by 5 pixel image.

Next zoom way into the image so you can see what you are doing.
Or just hit Ctrl+0 (zero) to zoom the image to fit the screen.

Now use your shapes or line tool to draw a simple design on your canvas.
I used a ellipse.

Assuming you have made a pattern that you will use for the scanlines.
Lets put it to work. Hit Ctrl+A to select the entire picture
With the image selected, go to Edit and choose Define Pattern.

It will prompt you to name this new pattern, name it whatever
and it will now be saved in Photoshop for future use.

Now lets do something with it.

Now apply it to an image. I am going to use this picture.
You can use whatever picture you would like though.

So open up the picture that you want to apply the scan lines to, and add an additional layer on top of it.

On the newly created layer, go to Edit/Fill and on the menu that pops up,
under contents from the drop down menu choose pattern.

Below this you will see another drop down menu next to the words Custom Pattern,
hit the little arrow and choose your newly created pattern

Now, You might wonder. . what the crap? Where did my image go.

Now you right click the layer and goto blending options.

Now you adjust the opacity.

To make it better I click the eye on layer one so I can see my original graphic.
I select are area where I don't want scanlines.

Now I turn the scanline layer back on you just click where the eye was.
Then hit your delete key on your keyboard.

Now I go back to the blending options and adjust the opacity.

It didn't turn out so great so, I will select the inverse and apply a filter.
Colored Pencil looks preddy shnazzy

I apply it to the scanlines layer.

Now I adjust the brightness.

Kewl. Kinda Looks Like diamond plate.

The End.