Mix approximately one cup of corn starch with approximately one-half cup of water. Do this in a bowl, simply using your hands to slowly mix it all up. As you mix, the mixture will feel kind of gooey or pasty.Grab a small handful of the goop, and roll it between hour hands... it acts like clay or putty.Let the blob sit in your palm, and it runs like a liquid. Squeeze it and it acts like a solid again.Cornstarch molecules are relative long and large. When you slowly stir them, or just let them be, they are able to slip past each other, and flow like a liquid.et the blob sit in your palm, and it runs like a liquid. Squeeze it and it acts like a solid again. Cornstarch molecules are relative long and large. When you slowly stir them, or just let them be, they are able to slip past each other, and flow like a liquid.