You can make homemade silly putty with a mixture of Sta-Flo liquid starch and white glue. Homemade silly putty made with liquid starch and white glue will not pick up images like commercial silly putty does, but it will still have the characteristic texture of the putty. Silly putty that is made with liquid starch and glue is nontoxic, but be careful when playing with it, as it can stick to clothes and stain them.
Add 2 cups white glue and 1 cup Sta-Flo liquid starch to the zip-top plastic bag. Seal the bag and shake it to begin mixing the glue and starch together.
Knead the glue and starch in the bag until it is thoroughly mixed. Add three drops food coloring to the mixture. Close the bag and knead it for five minutes.
Remove the silly putty from the bag. Pull and stretch the putty apart like you are pulling taffy. Keep pulling and stretching the silly putty to add air to it and dry it out for 10 minutes. When it starts to snap apart, it is done. Place the silly putty in an airtight container to store it.