1. First, open the paper document, place the cursor where you want to insert the cover, click the Insert menu, select the page layout, select the page background, and then select the page border.

2. Secondly, in the border and shading dialog box that pops up, select the page border tab and select the appropriate border style in the style drop-down menu.

3. Finally, select the appropriate border color from the color drop-down menu, enter the appropriate border width in the width text box, and then click OK to add the cover to the paper document.