How do I make a line transparent in IIllustrator CS5

[Byn]

Hi Everyone,

Image I've got a block of white and next to it a block of blue, then white etc, etc. What I want to do is draw a zig-zag line with the pen tool of say 1pt thickness and when I place it over the blue and white blocks the line is white over the blue blocks and blue over the white blocks. I hope I've made this example clear enough.

Thanks.
Byn

 

[carlow]

The best way to do this is the shape buider tool.

Draw the boxes, draw your zigzag.

Make the color of the line the same blue as the blue boxes.

Select the boxes and the line and use the shape builder tool.

When you move the shape builder tool over the zigzag line where there is a blue box, hold down the alt-key and click on the line part.

Do this for al the overlapped blue boxes.

good luck