Sure, I'd be happy to help you create a homemade face serum for dark spots. Here's a simple recipe using ingredients that are known for their skin-brightening properties:

Ingredients:
1. 2 tablespoons of Rosehip Seed Oil: This oil is rich in Vitamin C and fatty acids, which are known to help reduce hyperpigmentation and improve skin tone.
2. 1 tablespoon of Jojoba Oil: Jojoba oil is a great carrier oil that closely mimics the skin's natural sebum. It helps to balance the skin and carry the other ingredients deeply into the skin.
3. 5 drops of Lemon Essential Oil: Lemon oil is a natural skin brightener. It's rich in Vitamin C and citric acid, which can help fade dark spots. However, it can make your skin more sensitive to the sun, so always use a sunscreen during the day when using this serum.
4. 5 drops of Frankincense Essential Oil: Frankincense is known for its ability to rejuvenate the skin and improve skin tone.

Instructions:
1. In a dark glass dropper bottle, combine the rosehip seed oil and jojoba oil.
2. Add the lemon essential oil and frankincense essential oil.
3. Close the bottle and shake it gently to mix the oils together.
4. Apply 2-3 drops of the serum to your face at night after cleansing and toning, but before moisturizing.

Remember, it's important to do a patch test on your skin before applying any new product all over your face. Apply a small amount of the serum to a discreet area of your skin and wait 24 hours to see if any irritation occurs. If you notice any redness, itching, or burning, discontinue use.

Also, while this serum can help reduce the appearance of dark spots, it's important to remember that results can take time and consistency is key. Always protect your skin from the sun, as UV exposure can cause dark spots to darken further.