Create a rainbow in your journal using only images or papers that you have collected but *nothing* you have purchased! Junk mail, maps, brochures, postcards, stuff received in swaps, painted papers... all fair game. You might cut out red-orange-yellow-etc. things and glue, tape or staple them in a rainbow formation, an arc, a curve, straight lines or bent. Your rainbow might be fairly pale or quite vivid... or a mixture of the two... depending what papers you find!
Trying new things benefits your life, your brain and your creativity. But creative experimentation can be risky. It’s not a quantifiable risk, but you might go beyond your comfort zone and completely alter the course of a project you really kind of liked. At some point you will go too far. But you will not know how far you can go unless you push the limits of your art materials.