Using hyaluronic acid and tretinoin together can be an effective way to address multiple skin concerns. However, it is important to use them correctly to maximize their benefits and minimize any potential irritation. Here's a step-by-step guide on how to use hyaluronic acid and tretinoin together:

1. Cleanse your face: Start by cleansing your face with a gentle cleanser to remove any dirt, oil, or makeup. Pat dry with a clean towel.

2. Apply hyaluronic acid: Take a few drops of hyaluronic acid serum and gently massage it onto your face and neck. Hyaluronic acid is a humectant that attracts and retains moisture, helping to hydrate and plump the skin.

3. Wait for the hyaluronic acid to absorb: Give the hyaluronic acid a few minutes to fully absorb into your skin before proceeding to the next step. This will ensure that it can work effectively to hydrate your skin.

4. Apply tretinoin: Take a pea-sized amount of tretinoin cream or gel and dot it onto your forehead, cheeks, chin, and nose. Gently spread it across your face, avoiding the sensitive areas around your eyes, mouth, and nostrils. Tretinoin is a retinoid that helps to promote cell turnover, reduce acne, and improve the overall texture and appearance of the skin.

5. Wait for the tretinoin to absorb: After applying tretinoin, allow it to fully absorb into your skin before moving on to the next step. This usually takes about 20-30 minutes. It is important to note that tretinoin can cause skin sensitivity and irritation, especially during the initial stages of use. If you experience excessive irritation, you may need to reduce the frequency of application or consult with a dermatologist.

6. Moisturize: Once the tretinoin has absorbed, apply a moisturizer to help lock in moisture and further hydrate your skin. Look for a moisturizer that is suitable for your skin type and does not contain any ingredients that may interact negatively with tretinoin.

7. Sun protection: Lastly, it is crucial to apply a broad-spectrum sunscreen with at least SPF 30 every morning, as tretinoin can increase the skin's sensitivity to the sun. This step is essential to protect your skin from harmful UV rays and prevent any potential damage.

Remember, it is important to start using tretinoin slowly and gradually increase the frequency of application as your skin adjusts. If you experience excessive dryness, redness, or irritation, you may need to reduce the frequency or consult with a dermatologist for further guidance.