This chart can be used as a single motif on a washcloth, as a panel in a sampler, or in repeats around the circumference of a plain sweater. There are so many options and the choice is yours to make your St Patrick's Day knits special.
They can be knit into the piece in a separate color by stranding or intarsia, or stitched on with Duplicate Stitch later. Alternatively you can do the motif in Reverse Stockinette Stitch or Seed Stitch on a plain Stockinette background. Or you could even pick out the motif in beads.