Ensure the baking soda is finely ground; if not, use a grinder to refine it. Combine it thoroughly with cornstarch or arrowroot powder.
Gradually pour in 2 tablespoons of coconut oil and mix well using a fork.
Add a few drops of essential oil and blend again.
Finally, add the remaining coconut oil and mix until the mixture forms a smooth, paste-like texture.
Use a teaspoon to transfer the mixture into an old deodorant stick or a small jar, pressing it firmly as you go.
Chill it in the fridge for a few minutes, then store it in a cool place to prevent the coconut oil from melting. For an extra refreshing feeling, keep it in the fridge and enjoy the cooling sensation with every use.