There are two basic options for glue-free slime making: corn starch or powdered fiber. All slime recipes include a thickening agent to increase the viscosity of a liquid into a slime texture.
Glue and borax are a traditional combination for making heat-free slime; however, this method is not recommended for small children as they may decide it looks tasty. Borax is a detergent and may cause kids to get sick if eaten. Corn starch or powdered fiber recipes are a non-toxic alternative. Note any slime consumed in large quantities may cause a child to become sick. For this reason, it is important for an adult to monitor kids while making and playing with slime. Combine two parts corn starch, one part water, and food coloring into a saucepan and slowly heat to a boil while stirring. Allow the mixture to simmer for several minutes to achieve the desired thickness; ensure slime has cooled through before handling. If the corn starch slime becomes too thick, stir in a tablespoon of water at a time to thin. Use a microwave or stovetop to create fiber thickened slime. Mix 1 teaspoon of powdered fiber, also known as psyllium hydrophilic mucilloid, with 1 cup water and food coloring of choice in a large microwaveable bowl. Heat 4 to 6 minutes on high or until the mixture comes to a boil. Let it stand in the microwave for 2 to 4 minutes and then heat to boiling again. Repeat this procedure until the slime is the appropriate consistency. Cool the mixture before handling.