Add the cold water to a measuring cup. Sprinkle a packet of gelatin onto the water.
Allow the gelatin to sit for 1 - 2 minutes and mix.
Pour in the boiling water and stir well, ensuring the gelatin is dissolved. If the gelatin won't fully dissolve, add it to the microwave for 20 seconds at a time until it's dissolved.
Pour in the rubbing alcohol and stir well.
Step 3: Add colour and scent
Dip a toothpick or a skewer in the gel food colouring. Place the skewer in the gelatin mixture and stir until the colour is well combined.
Add 10 to 20 drops of essential oil in the scent of your choosing. Stir well.
Step 4: Pour into a jar and allow to set
Pour the air freshener mix into a clean jar.
Add a frog lid (the criss-cross wire top) to the top of the mason jar and secure it in place with a canning ring.Refrigerate the gel air freshener for 1 to 2 hours to set, or allow to set overnight at room temperature.