To make gooey Slime first get white glue, borax, food coloring, and water.
Take a cup of water and add one tablespoon of borax to it and stir. Take a half cup of water and add a half cup of white glue.
Add the two mixes together with some food coloring, mixing thoroughly (an easy, not too messy way to do this kneading is inside one of those zip-locking food-storage bags).
For an even grosser variation, mix in your favorite repugnant things, rubber maggots, eyeballs, flies, etc.
Store it in an airtight container to keep it fresh and slimy, and do what you can to keep it out of hair, carpets, furniture, and pets.