1) Break up the jelly cubes and place in a jug.
2) Melt the jelly with boiling water. Once all the jelly has mixed with the boiling water, top up with cold water and pour the jelly mix into glasses with straws. Add less water than the packet suggests so it sets a little firmer.
3) Leave for a few hours in the fridge for the jelly to set.
4) Find a squash that matches the colour of the jelly and serve in the same glass with a straw.