Step 1:

Shirt:
-Easiest thing to do is get a dogs shirt or sweater create your approximate measurements onto the blue and red and white striped fabric (add one inch all around for sewing).
-Then measure your dog for the sleeves and sew onto the rest of the shirt.
-Finally paint the star on the shirt

Step 2:

Shield:
-I traced and cut out the blue (bottom) and red (top)circles same size and sewed them together (using the iron on glue works just fine) leaving a small space to stuff in some cotton stuffing (old pillow case stuffing works).
--The back of the shield can be fasten on to the dog with a strap of the same blue fabric and add Velcro to the ends.
-Then glued on the smaller white circle and then red circle followed by the blue circle.
-Finally draw or use a stencil of a star with white fabric paint. Let it dry for a day.

Step 3:

Mask:
-Measure dogs head (attach an elastic on the back of the head for better fit).
-Cut wide holes for the eyes and snout.
-Cut out smaller holes for the ears.
-Finally paint an A on top of the mask.