Make up the jelly according to the packet instructions
Soak the gelatine sheets in cold water until soft. Heat 1 litre water in a pan until hot \(but not boiling\). Add the softened gelatine and stir until completely dissolved. Stir into the red jelly and mix together. Allow to cool.
Cut a lid from the watermelon – leave about 4cm intact at each end and cut about 1/3 – ¼ of the way down \- then scoop out the watermelon flesh
Peel the apples. Take one apple and, using a small sharp knife, cut out slots for the face making eyes, nose and mouth.
Cut small pieces of cucumber to make ‘eyes’ to fill the eye slots and push into position
Cut the second apple to make pieces to form the legs and arms and fix in to position using cocktail sticks on to the third apple. Make a small hole through the centre of the ‘body’ and poke the end of the jelly string through it securely so it stays in position.
Push 3 or 4 cocktail sticks in to the bottom of the watermelon, then carefully position the apples on top of them to form the alien
Use a small sharp knife to make a small hole in the side of the watermelon and thread the other end of the jelly string through it. Chill until set.
*Caution – please take care if serving to young children and be mindful of the sharp cocktail sticks inside the apples