It comes in a squeeze bottle. Simple borders and shapes are easy to add to a card and give them a nice finishing touch. You can use any color construction paper to do a border. A border on the top of the card is easy to do but gives the card a professional look. Glue it to the very top of the card.
Borders look best when they are in the same color family as the other elements of the card.
Cutting out basic shapes and gluing them to the front of the card is another creative idea. Another idea is to stencil shapes or designs. You can buy different stencils at any art supply. Then you put it on top of the card and with magic marker or colored pencil, color in the stencil design. The most important thing when creating a homeade card is that it comes from the heart.