Create a one-pixel border for ads
Publishers often require ads to have a one-pixel contrasting border.
Add a border when publishing the ad
When you publish an ad in Google Web Designer, the publish dialog gives you the option to add a border and pick the border color.
Add a border while building the creative
If you want to build the border into your creative before publishing, you can create a div that's slightly smaller than your full ad, then give it a border which will display outside the div and along the edges of the ad.
- Select the Element tool from the toolbar and click the Div element icon on the tool options bar. Make sure the Background color is set to "No color".
- Draw the div as a rectangle from the top left corner of the page (position 0,0) to the bottom right corner of the page so that the div is the same size as your page. (Use snapping to make fitting the div to the page easy.)
- While the div is still selected, open the Properties panel. In the Position and size pane, reduce the width and height values by two pixels each. For example, if your banner is 320x50, the div should be 318x48.
- In the Style pane of the Properties panel, set the border color so that it contrasts with the ad's background color, and set the border size to 1 pixel.