As an expert in skincare and clean beauty, I can guide you on how to prepare a salicylic acid ointment. Salicylic acid is a popular ingredient known for its exfoliating and acne-fighting properties. Here's a simple recipe to make a salicylic acid ointment at home:

Ingredients:
- 2 tablespoons of salicylic acid powder
- 4 tablespoons of a carrier oil (such as jojoba oil or grapeseed oil)
- 1 tablespoon of shea butter or cocoa butter (optional)
- 5-10 drops of essential oil (optional, for fragrance)

Instructions:
1. Start by sterilizing all the utensils and containers you'll be using to ensure cleanliness and prevent contamination.
2. In a double boiler or a heat-safe bowl placed over a pot of boiling water, melt the shea butter or cocoa butter (if using) and the carrier oil together.
3. Once melted, remove the mixture from the heat and let it cool slightly.
4. Slowly add the salicylic acid powder to the oil mixture, stirring continuously until it is well incorporated. Be cautious while handling salicylic acid, as it can irritate the skin and eyes.
5. If desired, add a few drops of essential oil for fragrance. Lavender or tea tree oil are good options due to their skin-soothing and antibacterial properties.
6. Transfer the mixture into a clean, airtight container and let it cool completely before sealing.
7. Store the salicylic acid ointment in a cool, dark place away from direct sunlight. It should last for several months if stored properly.

Important Considerations:
- Salicylic acid can cause skin irritation, especially in higher concentrations. It is advisable to start with a lower concentration (around 2%) if you are new to using salicylic acid.
- Before using the ointment, perform a patch test on a small area of skin to check for any adverse reactions.
- Salicylic acid is not recommended for pregnant or breastfeeding individuals, and it may interact with certain medications. Consult with a dermatologist or healthcare professional before using salicylic acid products.

Please note that this recipe is for informational purposes only and should not replace professional advice. It's always a good idea to consult with a dermatologist or skincare specialist before incorporating new ingredients into your skincare routine.