Gather your supplies & set each step up. The gelatin will set quickly.
I used a cat food can to put my air freshener in, because that's what I had lol Most people use a glass jar. Add 1-2 tsp of chosen oil to your container. If you are using food coloring, add now.
Add salt to a bowl & set aside.
The salt helps impede the growth of mold.
Heat water to boiling, add half to the salt to dissolve it & the other half to the gelatin, to dissolve. Best way to do the water is boil in a small pot & pour gelatin into pot & whisk to dissolve.
Combine the salt solution with the gelatin solution & give it a quick stir. Pour into your container & mix again to distribute the oil through the mixture.
Let sit for 24 hours at room temperature, undisturbed, to set up. Place where you need a lil smell good :) From what I read, it will last 4-6 weeks.