To make a water-based gel, you need a gelling agent. Carbomer 940 is a popular cosmetic ingredient that can be used to make water-based gel. It is sold in powder form and you can buy it from cosmetic labs and some vitamin stores. Methylparaben is an anti-irritant agent and water-soluble anti-microbial to add to the solution. Once you have these ingredients, you will only need water to make your gel.

Pour 25 oz. of water into a pot and warm it to approximately 120 degrees Fahrenheit.

Add 1/4 tsp. of methylparaben and stir well.

Put 1 oz of Carbomer 940 into a 32-oz. jar and add the water. Mix regularly as you're adding the water. You may see Carbomer particles floating to the top until it is completely dissolved. This is fine. Let the mixture sit until the carbomer fully dissolves into the water. Once the carbomer completely dissolves, you will have a clear, uniform gel.