Stand watermelon on end; cut thin slice off bottom to make it level.
Cut top third off melon.
Using cup as guide, trace scallops around top outside edge of melon.
Carve scalloped edge, following pattern.
Scoop out fruit; serve later.
Chill melon shell.
Combine Hawaiian fruit punch, fruit juice concentrates, and water.
Pour over ice in melon bowl.
Resting bottle on rim of melon, carefully pour ginger ale down side; mix with up-and-down motion.
Float orange and lime slices.
Twine melon with ivy leaves, holding with toothpicks