How to Make Thick Slime

• Make thick slime using glue, lotion, Borax, and/or liquid starch.
• Use a more concentrated Borax activator when making slimes for a thicker consistency.
• Add oils like baby oil or glycerin to slime mixtures for a glossier and smoother texture.

Using Borax and School Glue

Combine 1 tbsp (15 mL) of Borax with 1 cup (237 mL) of water. Borax acts as a slime activator, causing the glue and other ingredients to stick together and form a spongy goo. A stronger activator, like this one, will help the slime thicken. If you don’t have Borax, try using contact lens solution (one that contains boric acid) as a substitute. Simply use 1 to 2 tbsp (15 to 30 mL) of contact solution in the slime instead of the Borax and water mixture.

Pour ½ cup (119 mL) of school glue into a new mixing bowl. Glue acts as the slime’s base, and although school glue isn’t thick, your strong activator will cause it to thicken later. Opt for a classic white glue for a milky color or a clear glue for clear, transparent slime. Try using a colored or glitter school glue to make your slime even more fun.

Add ½ cup (119 mL) of water to the mixing bowl. When making this type of thick slime, always use a 1:1 ratio of glue and water. This will create the perfect moldable and stretchable texture. Not adding enough water could cause the slime to crumble and become cakey, while adding too much could cause it to thin out.

Squeeze food coloring into the mixture to change its color. If you used a clear or white school glue, consider adding food coloring to turn it a different color. Start with one drop and add more until you get your desired color. Think about adding other mix-ins like glitter or miniature styrofoam balls to add more texture to your thick slime.

Mix the ingredients together until everything is combined. Use a spatula, spoon, or craft stick to ensure that everything is mixed together thoroughly before moving on to the next step.

Add the Borax solution a teaspoon (5 mL) at a time. Put a splash of your premade activator into your slime mixture. Use your mixing utensil to stir it in completely. The consistency of your slime will start to change as the activator reacts with the other ingredients—clumping together and moving away from the bowl. The more activator you use, the thicker your slime will be. Try not to add too much activator to your slime, as this can cause your slime to become stiff and break. If this happens to you, simply mix in some extra glue.

Knead the slime until it takes on your desired thickness. Now comes the fun part! Dump out your slime mixture and squish, squeeze, pull, and fold it until it begins to take shape. The longer you work your slime, the stronger it’ll become. Store your slime in an airtight container for up to 2 weeks.

Adding Lotion to Glue-All

Pour 1 cup (237 mL) of Glue-All into a mixing bowl. Glue-All is the perfect base for your thick and glossy slime because it clumps together when combined and activated with other ingredients. School glue could be used as a substitute, but the texture may not be as thick or moldable. If you’d like extra glossy slime, use ½ cup (119 mL) of Glue-All and ½ cup (119 mL) of clear glue.

Add about 2 tbsp (15 mL) of lotion to the glue. The lotion acts as a softener and helps the slime stretch. Roughly 2 pumps or squeezes of the lotion will be enough. Try using a scented lotion to make your slime even more soothing. Consider the color of your lotion before adding it, as the color may affect the color of your slime.

Squirt a small amount of baby oil into the bowl. Adding too much baby oil could cause your slime to be too slick, so just add a dash. Aim for around ½ tsp (2.5 mL).

Add around 2 tbsp (15 mL) of hair conditioner into the mixture. Like lotion, conditioner adds a soft, smooth texture to your slime while keeping it nice and thick. Only 2 to 4 pumps or squirts are needed. Consider using a scented conditioner that matches your lotion's scent.

Mix all the ingredients until everything’s well combined. Use a spatula, craft stick, or plastic spoon to bring everything together. It’s better to over-mix your slime at this stage than to under-mix it! Make sure all the ingredients are mixed evenly, as this will help the activator adhere to the mixture. Try adding a few drops of food coloring to your mixture for even more fun.

Stir a Borax activator solution into the mixture in small increments. Mix together 1 tsp (5 mL) of Borax in 1 cup (237 mL) of warm water in a separate container or bowl until all the Borax is dissolved. Then, pour the Borax activator into your slime mixture in 1 tsp (5 mL) increments until your slime reaches the desired consistency. The mixture will clump up and become stringy, but the more you stir, the more solid it’ll become. Be patient, and don’t be afraid to use your hands! The more activator you add, the denser your slime will be. You may use all of the activator or you may not use much at all, and that’s okay!

Let the slime sit for at least 24 hours in an airtight container. Believe it or not, slime isn’t fully activated for at least a day. Give the slime a day to sit, as this will help it be its glossiest. Store the slime in an airtight container for 2 to 3 weeks or until it becomes hard.

Mixing Liquid Starch with Glue

Pour ½ cup (119 mL) of school glue into a bowl. To achieve that Oobleck or Gak look, opt for a white school glue as it will help the slime’s color pop later on.

Add ¼ cup (59 mL) of water to the bowl. Stir the glue and water together. This will be the base of your slime.

Drop in food coloring or glitter to make the slime your own. Once you’ve combined the glue and water, it’s time to get creative! Add green food coloring to replicate Dr. Seuss’ Oobleck or blue or orange to make your own 90’s Nickelodeon Gak. Try tossing in a pinch of glitter for a little sparkle.

Add ¼ cup (59 mL) of liquid starch to the mixture gradually. As you stir, pour in the liquid starch little by little. This is the activator for your slime. Start with 6 tsp (30 mL), stir, and then add the rest. Keep mixing until the slime doesn’t stick to the sides of the bowl. If you don’t have liquid starch, make a substitute by combining 1 tbsp (15 mL) of cornstarch with ¼ cup (59 mL) of water.

Knead the slime with your hands. Scoop the slime up in your hands and begin squeezing and stretching it. Notice how the slime thickens up the more you play with it and becomes more of a liquid when you stop. Store this thick slime in an airtight container for 3 to 4 weeks or until it dries out.

Combining Glue and Glycerin

Pour ½ cup (119 mL) of school glue and ½ cup (119 mL) of Glue-All in a mixing bowl. This is the base of your slime, and the combination of glue types makes for an extra thick slime. If you’d like to make more slime, stick to a 1:1 ratio of school glue and Glue-All. Try using a plastic storage container with a lid to make your slime. This way, you won’t have to transfer it to an airtight container or cover it later.

Add ½ tsp (2.5 mL) of glycerin to the glue and mix. Glycerin makes the slime smooth, stretchy, and glossy, but don’t add too much! The oil can separate and leave a film on your finished slime. Mix all the ingredients together with a craft stick or spoon until everything is well combined. Don’t get discouraged if it takes a while to mix everything together—that’s perfectly normal! Thick slime requires a bit more mixing than ordinary slime.

Mix food coloring into your mixture for a bright color. Leave your slime a milky white, or add a drop or two of food coloring to the mix. Start with one drop and add more as you stir, if needed.

Stir in a 7:1 Borax water solution until the slime clumps together. A stronger activator with a 7:1 ratio helps the slime thicken without extra ingredients. Mix together a solution of 7 tsp (35 mL) of Borax and 1 cup (237 mL) of hot water, and add it to the glue and glycerin mixture in 1 tsp (5 mL) increments. Keep mixing until no strings are in the slime—feel free to use your hands.

Let the slime sit in an airtight container for 24 hours. Leaving the slime to rest for a few days will reveal its true consistency and shine as the activator fully develops. After a day goes by, pop your slime out of the container and get squeezing! Keep your slime in its container for up to 3 weeks or until it starts drying out.