Fill a large clear pitcher or punch bowl about halfway with ice cubes. Clear ice (made from boiled water) gives the best visual effect, but regular ice is fine.

Pour the cranberry juice slowly down the side of the pitcher. This forms the bottom layer because it has the highest density (sugar and solids). It will settle at the bottom.

Next, carefully pour the orange juice over the back of a spoon held just above the cranberry layer. This slows the pour and keeps the layers separate. Orange juice is less dense than cranberry, so it floats.

Slowly pour the pineapple juice over the back of a spoon, just above the orange layer. Pineapple juice has a similar density to orange juice, so it may mix slightly; that's okay. The key is a slow, gentle pour.

For the blue layer: pour the blue sports drink or blueberry juice over the back of a spoon. If using blueberry juice, note it may be slightly thicker. Sports drinks are lighter and will stay on top of the pineapple layer.

Finally, pour the lemon-lime soda over the back of a spoon. This is the lightest layer and will float on top. If using white grape juice, pour it between the pineapple and blue layers, or use it as a top layer instead of soda.

Garnish with fresh fruit: a few strawberry slices, orange wheels, pineapple chunks, and blueberries. Serve immediately with a ladle or long spoon for stirring.

To maintain the layers, do not stir until serving. Each person can stir their own glass, or you can stir the whole punch just before serving, which will turn it a uniform reddish-purple color.