I've made hundreds of batches of slime testing kits before launching Slime, and the #1 mistake I see is people rushing the activator.

Most tutorials tell you to just "add activator until it's not sticky." That's how you end up with rubbery, over-activated slime that won't stretch.

Here's the fix: add your activator in small splashes (a teaspoon at a time), knead for a full 60 seconds between each addition, and stop the second it clears the sides of the bowl — even if it still feels a little tacky in your hands. It firms up over the next few minutes as you knead. Patience beats more activator every time.

Second biggest mistake: adding glitter or foam beads before the slime is fully formed. Mix-ins should go in last, once your base is smooth and stretchy — otherwise they clump instead of distributing evenly.

Just put together a bulk kit with everything measured out (glue, activator, and a curated set of add-ins) so you can skip the guesswork. Happy to answer any slime-chemistry questions in the comments.