Creating your own DIY vitamin C serum can be a fun and cost-effective way to incorporate this powerful antioxidant into your skincare routine. However, I would recommend avoiding the use of coconut oil in your vitamin C serum. While coconut oil is a popular natural ingredient, it may not be the best choice for a vitamin C serum due to its comedogenic nature. This means it has the potential to clog pores and cause breakouts, especially for those with acne-prone or sensitive skin.

Instead, I suggest using a carrier oil that is lightweight and non-comedogenic, such as jojoba oil or squalane oil. These oils are easily absorbed by the skin and won't clog pores.

To create your own DIY vitamin C serum, you will need the following ingredients:

1. L-Ascorbic Acid (Vitamin C): Look for a high-quality, pure form of L-ascorbic acid powder. This is the most effective form of vitamin C for skincare.

2. Distilled Water: It's important to use distilled water to ensure the purity of your serum and prevent the growth of bacteria.

3. Aloe Vera Gel: Aloe vera gel has soothing and hydrating properties, making it a great addition to your serum.

4. A carrier oil of your choice (e.g., jojoba oil or squalane oil): This will help nourish and moisturize your skin.

5. A dark glass bottle with a dropper: Vitamin C is sensitive to light and air, so storing your serum in a dark glass bottle will help maintain its potency.

Here's a simple recipe to get you started:

1. In a clean bowl, mix 1 teaspoon of L-ascorbic acid powder with 2 teaspoons of distilled water. Stir until the powder is completely dissolved.

2. Add 1 tablespoon of aloe vera gel to the mixture and stir well.

3. Finally, add 1-2 drops of your chosen carrier oil and mix thoroughly.

4. Transfer the serum into a dark glass bottle with a dropper for easy application.

Remember, vitamin C serums are most effective when used fresh, so it's best to make small batches and store them in a cool, dark place. Additionally, it's important to perform a patch test before applying the serum to your face to ensure you don't have any adverse reactions.

If you prefer a more complex formulation or need specific guidance based on your skin type, it's always a good idea to consult with a dermatologist or skincare professional.