2 tbsp PVA glue
2 tbsp water
1 drop food colour
2 tsp borax solution (ie: 1 tbsp borax to 1 cup warm water, stirred
Combine glue & water in a bowl, stirring with spoon till completely
Add a drop of food colour. Add borax solution and stir.
It will start immediately to clump together.
Add a little more borax solution, & keep stirring until all the liquid
Play with it!
Borax is available from Boots and other