Yarn Heart Cards How-To: Colored cardstock, scissors, tape, needle, plastic child-safe tapestry needles, colored yarn  Cut a 4&quot;x8&quot; piece of card stock punch holes in the card with a needle. Thread a tapestry needle with colored yarn and knot the end. Starting from the inside of the card, stitch yarn from side to side. Finish by knotting on the inside of the card and trimming any excess yarn.