One light blue (or green) marker and one bright red marker.
Red cellophane paper or a transparent red plastic sheet. Scissors and Tape/Glue: To create the "decoder lens". Step-by-Step Instructions Prepare the Decoder Lens (5–10 Mins) DECODE RED - Part 222:26 Min
Cut a piece of slightly larger than the hole and tape or glue it over the opening. This will act as your "secret lens" that reveals the hidden text. Write the Secret Message (5 Mins) One light blue (or green) marker and one bright red marker
If you don't have red cellophane, you can create a "heat-decode" paper using . Write your message with juice and a brush; once it dries (about 15–20 minutes), hold it near a heat source like a lightbulb or iron to turn the writing brown and "decode" it. Write a Secret Message with Matt! Write your message with juice and a brush;