Make hat. Using craft knife, trim sugar cone to 3 in. tall. Place on cooling grid placed over parchment paper.
Melt Bright White Candy Melts candy according to package instructions. Pour small amount melted white candy over sugar cone. Chill until set, about 10 to 15 minutes. Reserve remaining melted candy.
Using candy colors, tint ¼ cup melted white candy yellow, green and orange. Tint ¼ cup melted white candy teal by combining Blue and Green candy colors. Reserve remaining candy white.
Prepare decorating bags, separately, with yellow, green, orange and teal candy. Cut ¼ in. tip in each bag. Alternating colors, pipe small dots on hat. Chill until set, about 10 minutes. Reserve remaining melted yellow candy for later step.
Using craft knife, make small hole in large yellow gumball. Using remaining melted yellow candy, attach gumball to tip of hat. Chill until set, about 10 minutes.