Gather supplies: white school glue, water, baking soda, liquid contact lens solution (boric acid), food coloring (optional), glitter (optional), mixing bowls, spoon, measuring cups
In a bowl, mix glue and water (typical ratio: 1/2 cup glue + 1/4 cup water)
Add food coloring and/or glitter if desired
Sprinkle in baking soda (start with 1/4 teaspoon)
Stir until evenly mixed
Add liquid contact lens solution slowly while stirring (typical amount: 1–2 tablespoons)
Continue adding contact lens solution until the slime pulls away from the sides and becomes stretchy
Knead the slime with clean hands until smooth
If too sticky, add a small splash of contact lens solution and knead
If too stiff or dry, knead in a tiny bit of water or a small amount of glue
Store in an airtight container when not in use