Slice 1/4 inch off bottom of watermelon, lengthwise, to create a stable base. Use pencil to draw zigzag lines for basket opening. Using paring knife, make cuts through rind.
Carefully remove top section, pull out large chunks of flesh and cut them into 3-by-3-inch squares. Trim 3/4-inch-thick slices off squares to use for cutting out stars with 1-1/2- to 3-inch star-shaped cookie cutters.
Use ice cream scoop to remove flesh from inside basket and cut scoops into quarters for fruit salad. Place in bottom of basket. Add honeydew and blueberries; stir to combine.
Cut out white stripes from honeydew. Garnish top of fruit salad with watermelon stars, honeydew stripes, and blueberries.