Yes, just buy fabric to match colors. Be careful of the brand of fusible you use. I personally would recommend Misty Fuse because it does not change the hand of the fabric.
Basically, decide on the background fabric. Buy fabrics to match the colors for the shield. Fuse Misty to the *wrong* side of the shield fabrics. (Use parchment paper to protect your iron and board.) I would then trace the shield onto freezer paper and iron the freezer paper to the *right* side of the shield fabric. Then I would cut freezer paper pattern and fused fabric out together with a good pair of scissors. Once you have all of the shield pieces cut out, remove the freezer paper, place them on the background fabric, and iron to secure them in place (again using parchment paper for protection).
Once everything is fused, you want to sew all the edges. You can zigzag around all of the edges, or straight stitch inside the edges (which will allow the edges to eventually fray with washing), or you can blind hem stitch around the edges. You can choose to use an invisible thread (I like YLI nylon monofilament), or you can use regular thread.
Alternatively, you can wait until the quilt is sandwiched and simply stitch around and/or over all of the applique edges as part of the quilting.
Google Misty Fuse and other fusibles to see some step-by-step pictures of how to fuse for quilting. If you don't use Misty Fuse (often only available online; I got mine from Amazon), my second-choice recommendation would be Steam-a-Seam Light (widely available in JoAnn's). Some fusibles cannot be stitched through, and some stiffen the applique fabric a lot; avoid those.